martedì 28 giugno 2016

Recupero Dati Hard Disk Esterno | iRecovery


How To Choose the Best Data Recovery Software

How To Choose the Best Data Recovery Software

There are plenty of ways for you to lose data. Most often the reason is accidental, which can include anything from deleting the wrong file to improperly disconnecting an external hard drive or device. In just a few missteps, your only copies of vital records or cherished family photos can be lost. And regardless of how it happened, you need the information back.
We’ve reviewed what we determined to be the top ten data recovery software products available. Along the way we learned that not a single one of them is perfect for every situation; in fact, you will likely have to run the software against your device multiple times to get the best results possible. The best software though, will give you a good shot at retrieving a significant portion of your data. To learn more about data recovery and data-loss prevention, see our articles on disk recovery software.

Data Loss: How It Happens and What to Do About It

Do-it-yourself data recovery is a significant investment of time and money. It’s your willingness to make the investment that makes it critical for you to understand the two primary types of data loss before you begin: physical and logical. Physical damage is indeed the most extreme cause of data loss. Typically, you will have plenty of signs that a something is wrong, such as a subtle ticking sound coming from your computer or obvious external damage. Be aware that if you’ve lost files because a disk has been physically damaged, recovery software will not solve the problem. If your computer doesn’t recognize your drive or device, simply refuses to go past the BIOS (basic input/output system) system screen during startup, or is making unusual noises during operation, it does need to be repaired by a professional. Please look at our hard drive recovery service review page if your computer experienced any of those symptoms prior to your data loss.
If you're hard drive hasn't suffered from physical damage, then you've experienced logical data loss. This occurs when the logical process that the operating system uses to access the file has been altered or corrupted so that you can't access the file. The two most common logical data loss scenarios occur when you've lost files through accidental deletion or a reformatted drive. In both cases, the greatest danger to a successful recovery is overwriting the file with new data. You know you’ve suffered logical data loss if your computer can still recognizes your drive but simply doesn’t see partitions or the files you need.
With logical data loss, your computer has lost its reference to where the files are stored on the drive. Frequently, this is a user error issue. It begins with deleting a file. Recovery from here is normally as easy as going to the Recycle Bin to undelete the file. If the loss is only noticed after the bin has been emptied, the solution is less straightforward. Files can also be lost if your computer is improperly shut down or if a memory storage device is removed during a write operation. In the industry, these are referred to as lost files since their reference to your drive's file table has been lost. The files are still there. Your computer just doesn’t know where to find them. Depending on the type of device these lost files were stored on, most recovery software should be able to find them, so long as they haven’t been overwritten.
When your system loses the reference to where files are stored on your device, your computer recognizes it as available for new data to be written, so it may end up storing new data over the old. There is an excellent chance of this happening if more than a few minutes of running time has passed since clearing your Recycle Bin. It can happen that fast.
You cannot recover an overwritten file because the ones and zeros that make up the file have changed. However, you can recover partial files. These are sectors or blocks of a file that haven't been overwritten. Recovery software takes those surviving blocks, or fragments, and puts them back together. Most of the time, however, this results in incomplete files being returned.
Finally, there are those files left behind on a disk that has been reformatted. This can happen when you decide to repurpose an old drive or device only to later realize that you forgot to back up the files you wanted to keep beforehand. Fortunately, data recovery software can help with these more difficult recovery scenarios, but with varying success.

Data Recovery Software Review: How We Tested, What We Found

Because different drive and device types store information differently, each storage medium provides a unique challenge for recovery software packages. For example, a hard disk drive (HDD) stores files until they’ve been deleted, allowing them to be overwritten when new data is saved, but a solid-state drive (SSD) erases the block upon which the data was stored as soon as you issue the command to delete the file. Furthermore, the common microSD card used in phones, MP3 players and cameras is normally TRIM enabled, meaning it intentionally destroys the data stored on the device as soon as its been deleted. Because of these differences, we tested each recovery software on three drive types: HDD, SSD and microSD card.
In establishing our methodology, we strove to mimic the common types of data loss that occur. Disk recovery is not a quick process. In fact, even the fastest program we tested would have taken 55 hours to complete full scan of a 1TB drive. To manage these concerns, we created partitions on our various devices, so each program could be tested on a smaller amount of data.
We also constructed data sets that consisted of picture, document, video and music files – as these are typically the types of files users keep stored in their Windows Libraries folder. In order to track our success, we created separate data sets for each type of data loss to be tested. For the matter of testing, it was important that each set be designed to limit the amount of free space between the data set and the partition wall.
We then set about recreating the specific types of data loss mentioned above. Making lost files to recover involved saving files to the partition before deleting them and emptying the Recycle Bin. In testing recovery rates for data lost to reformatting, we intentionally reformatted our test devices before scanning them. Each recovery program was tested under identical conditions against the same data sets.
Each software package features raw data recovery, which means it scrapes every bit of available data from the drive during the initial scan. All of the brands we tested do have automated features that let you search for missing data by file type or other identifiers. We did test these automated features as part of our evaluation, but found them to be mostly unreliable across the board. For our final results, we tested each software by its raw data recovery capabilities to get the best evaluation of its recovery rates.
Top Ten Reviews seeks, whenever possible, to evaluate all products and services in hands-on tests that simulate as closely as possible the experiences of a typical consumer. We obtained some of the software in our comparison through donations from the respective companies, and others we purchased through retail outlets. The companies had no input or influence over our test methodology, nor was the methodology provided to any of them in more detail than is available through reading our reviews. Results of our evaluations were not provided to the companies in advance of publication.
Below are the general observations and takeaways from our testing of disk recovery software.
Recovery Software Success Varies by Data Loss & Drive Type
In all, our testing revealed that no product excelled at all recovery challenges. We found that some did better at recovering lost pictures and video files, while others did remarkably well at resurrecting reformatted MS Office files. Some were more successful at recovering from hard disk drives, while others were surprisingly adept at microSD card recovery. Overall, we collected 48 data points on each reviewed software package, and we discuss the strengths and weaknesses of the programs in their respective reviews.
As expected, most software packages had little trouble recovering a fair percentage of the lost files. Among all the software we tested, the average recovery rate for lost files was close to 100 percent from both hard disk and solid-state drives, but overall they averaged only a 50-percent recovery from a microSD card. The average rates for recovering files from a reformatted drive were more consistent across the devices we tested, with the average recovery being 50 percent of the files from a HDD and SSD, and 46 percent from a microSD card.
Furthermore, it's important to note that the recovery rates within each product varied greatly depending on which storage device was being scanned and the type of data loss being recovered. For example, one program found 100 percent of the lost files from a solid-state drive but only 63 percent of the lost files from a micro SD card. That same software was also only able to find 33 percent of the files lost to a reformatted SSD, but it was still able to find 99 percent of those same files on a microSD card.
Not All Found Files Are Recoverable
It is not uncommon at all for recovery software to report finding thousands of files, but many of them are actually empty or unusable fragments. Quite often the files returned in our testing were zero-length, meaning they were little more than a header without content. Some pictures that opened would only be half complete. Others simply would not open at all. To ensure the recovery rates we reported from our testing referred to useable files, we used an open source CHECKSUM tool to identify complete files. For example, in one round of testing, a disk recovery product reported that it had returned 11.9GB of information, which turned out to be just 1.24GB of usable data after being verified with the CHECKSUM tool.
If You Don’t Succeed, Try Again
One thing that was consistent in testing the performance of these data recovery products was that they were not consistent in their results. We frequently found different results with each recovery attempt. Three of them did produce nearly identical results to their respective previous test runs, but never on more than two consecutive passes. A few on the lower end of our review returned no files in one scan for lost files only to report finding 100 percent on the next. To mitigate the inconsistencies, we ran three rounds of testing on each program in order to report the best recovery rate for each.
Extra Features: A Blessing and a Curse
Some programs have features beyond the basic file recovery utilities. More than a few of these programs – such as our top three choices, Data Rescue PC3, Ontrack EasyRecovery Professional and Stellar Phoenix Windows Data Recovery Professional – work with or offers access to your hard drive’s Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T.) utility. Along with other measurements, such as internal temperature, this utility tracks the progression of bad blocks to warn you of impending drive failures. While having access to the S.M.A.R.T. utility is handy, you do not need third-party software to access it. However, programs that work with the utility often offer a useful interface for accessing the tool.
Be aware, however, the S.M.A.R.T. utility is not entirely reliable technology. A 2007 Google field study, “Failure Trends in a Large Disk Drive Population,” which monitored 100,000 hard drives, found that 56 percent of failed hard drives failed without offering any warning from the S.M.A.R.T. utility.
A few programs allow you to boot your computer from a pre-OS state. Of the data recovery software we reviewed, only Data Rescue PC3, R-Studio, Power Data Recovery Personal and Salvage Data Recovery offer this feature, which allows you to start your computer and perform a recovery operation in a basic environment that won’t threaten your lost data. This does mean that you will need to start your computer from an external media and be able to save your recovered information to a destination that is considerably larger than your hard drive, such as an external hard drive or network-connected drive, as most data recovery programs will return several times the amount of the data lost on the drive. It was not uncommon for us in our testing to get our data returned as much as ten-fold.
Others programs, such as Data Rescue PC3, Stellar Phoenix Windows Data Recovery Professional, R-Studio and Recover My Files Professional, have complex tools for network recovery operations. For example, Stellar Phoenix Windows Data Recovery Professional and R-Studio feature tools to help you manually reassociate file fragments with a disk and hex editor, respectively. However, if you are not familiar with using these types of tools, there is a risk of irreversibly damaging your data. If your data loss requires work beyond your skill level, you should consider seeking the help of a qualified hard drive recovery service.

Data Recovery Software Review: What Else Is Important?

Data recovery generally takes a lot of time. While successfully recovering your data is the most important consideration, your time investment is also something to take into account. When manufacturers advertise recovery speed, they are generally speaking in terms of scanning alone. Rarely do they take into account the amount of time spent recovering, which can take significantly longer. The act scanning is just the software collecting fragments of information from your disk on the block level. The recovery portion is where the actual work comes in. After collecting the information, the software must find a way to match file fragments. Often times it can do this with remaining header information in the file, but also sometimes must identify patterns in the fragment to match with patterns in other fragments. In our testing, we logged the process from the time the software started scanning to when it finished recovering.
Recovery Speed: Speed Doesn’t Correlate With Efficacy
We found no correlation in our testing between how fast a program works and its recovery rate. In fact, while Stellar Phoenix Windows Data Recovery Professional logged some of the longest scan and recovery times and had the best recovery rate, Data Rescue PC3 had only average recovery speeds, yet it boasted the second-best recovery rate. All else being equal, it's worth a little extra time investment if it means you have a better chance at recovering your missing data, but be aware that slower isn't always more thorough, and faster isn't always less so.
Many disk recovery software packages have features to help reduce the amount of time you will spend scanning and to make the overall recovery process easier. A feature like disk imaging goes a long way to keeping you from further damaging the data. Primarily with solid-state devices, each scan can damage the data. Also with mechanically failing devices, you do run the risk of it failing altogether simply because the scanning process is so intense. Creating an image of your drive or device gives you a scannable bit-for-bit copy that allows you to scan time and again without worrying about permanently affecting your data. An image is also useful if you need to get your computer back up and running right away.
Because scanning can take so long, pause and save features give you time to take a break from watching a timer and file counter, and let you move on to other tasks that might have more of an immediate priority. Other features can also reduce the time you’ll spend waiting by letting you search for only particular file types, names and even dates; however, we experienced diminished returns with these features. While these extras did not actually improve the success of our recovery, they can help make the process more manageable.
Help & Support: Look For Remote Assistance & Detailed Information
When it comes to data recovery, you need a company that does more than stand behind its product. Most of these services offer great help and support, but a few companies, like Ontrack EasyRecovery Professional and Stellar Phoenix Windows Data Recovery, go the extra mile by offering remote assistance for your recovery. Many also offer detailed user manuals and endless forums for help and support.

Data Recovery Software Review: Our Verdict & Recommendations

Disk recovery software can be costly, but a professional disk recovery service costs far more. While there will be times you may want to consider calling in a professional, you can save yourself a lot of money with do-it-yourself recovery software, provided the damage isn't too great. Clearly, no single recovery application can do everything, and the best software choice will depend on your specific data recovery needs.
Among our top three choices, we found a great combination of recovery rates, features and support options. Aside from its high recovery rate, the Gold Award winning Data Rescue PC3 has tools that let you work across your home network and even let you recover your primary hard drive in a pre-OS state. The developer has a solid foundation real-world data recovery situations, and the company is so confident in its product that it will discount the cost of its software from the cost of its hard drive recovery services if it turns out you need them.
The Silver Award winning Ontrack EasyRecovery Professional had some of the best recovery speeds and one of the highest rates for recovering lost files from a solid-state drive. The Bronze Award winning Stellar Phoenix Windows Data Recovery Professional, however, had the best overall recovery rate. Its data recovery engine worked best across all three of our test devices. It also features a disk editor which allows you to help it identify unfamiliar file types.
It's worth noting that while Data Recovery Wizard Professional from EaseUS had the third best recovery rate among the programs we reviewed, it fell short of others in the area of additional features. Much of the software we reviewed is designed for basic data recovery tasks. For the more technically inclined, R-Studio offers advanced networking capabilities and built-in hex editor. We found value in each reviewed software package, and each review explains in depth exactly how each one excelled.
Article source: http://data-recovery-software-review.toptenreviews.com/#sthash.bWNSwYSy.dpuf





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