Comodo Time Machine: roll back your PC to a previous state, including every file on every partition


Comodo Time Machine is a free program that can roll your system back in time, on-demand, to a previous state. It provides the ability to “undo” any kind of undesirable event, such as a virus or malware infestation or any event or events that might have caused your PC to become too cluttered, slow, or unresponsive, by giving you the ability to revert back to a baseline state or to a snapshot of the system taken before the problem started. It also provides the ability to recover any data or files that may have been accidentally deleted, saved-over, or damaged in any way.

Comodo Time Machine is unlike Windows restore in that it doesn’t just affect the registry and system settings, but transforms your entire system including your files and everything on your hard drive. What is interesting is that if you do revert back to an earlier state, the software will still preserves the “future” point which you reverted from, allowing you to reclaim any files that had been changed or added if you need to.

Comodo Time Machine takes regular scheduled automatic snapshots, making it possible to use the protection it provides while on auto pilot, so to speak, without having to be managing it manually it at all times.

Comodo Time Machine Screenshot1Comodo Time Machine Screenshot2

[Update 3/24/2010: after publishing this review and reading some of the user comments I recommend that you NOT install this program without taking an image of your hard drive first. Some good imaging freeware are Paragon Backup & Recovery, DriveImage XML, and Easeus Todo Backup. ] If you do not know what a disk image is then definitely stay away from this program.

Imagine being able to restore yesterday’s version of a file that you had just accidentally saved over or permanently deleted; Imagine being able to install and test all sorts of software whilst having the option to revert back to a previous stater; Imagine being able to easily get rid of the nastiest virus or malware infestations, even those that would normally prevent you from booting the system back again. Comodo Time Machine makes all of this possible, but it does so at the potential cost of gobbling up a significant chunk of hard disk space.

To be clear, I find this program to be very compelling and extremely interesting, but would stop short from recommending it for every user. Comodo Time Machine can only do what it does given enough hard drive space that it can store and preserve all the different versions of files that change on your hard drive, including any large files that you might delete or move after use, such as videos or other media files. Everything will be preserved, at least across different snapshots. Which makes it more suited to some situations than others.

Here’s a list of scenarios where Comodo Time Machine might be an excellent fit.

  • Users who have large amounts of unused hard drive space. Comodo Time Machine recommends 10 gigs of free space and 4 gigs at minimum; however, if you download a lot of large media files on your computer you may need multiples of that.
  • Public computers: such as those in libraries, internet cafes, etc.
  • Software developers and testers: will find this to be extremely convenient; they can rollback deployed software without uninstalling. Software reviewers like myself would also find it extremely useful.
  • Computers used by novice users: i.e. you can put it on grandma’s computer or the computer used by the kids, etc, and know that you can restore files they accidentally delete or rollback any dubious software or malware that they accidentally install.

Cases where Comodo Time machine is not a good fit:

  • If your PC is stretched for hard drive space: Comodo recommends that you have 10 gigs available, and I would strongly discourage you from installing if you have less. Moreover, do not install if you have these spare gigs but might conceivably fill them up at a later point after installation.
  • If you download a lot of large files on a regular basis: because of its promise to roll back your system to any saved snapshot, these large files will in fact be saved into the snapshots and remain on your hard drive even after you move or delete them. On my system, because I download large media files (read: torrent movies) it took only 3 snapshots to fill the 10 gigs that this program had allocated for itself. Once I got to that point I could no longer do anything whatsoever on my PC until I had either (a) removed some snapshots and rebooted, or (b) reset my base snapshot to the current snapshot and rebooted. Both of these methods can end up freeing up gigabytes for Comodo Time Machine to work with.

With the above in mind, here is a list of PROs and CONs that can shed light on why this is a brilliant program but also why you should be careful if you want to install it:

What I like about this program:

  • It can restore previous versions of files: i.e. files that have been accidentally deleted or even saved over. How cool is that?
  • Snapshots are taken in manner of seconds: quite unlike, for example, a re-imaging of your hard drive, which can be involved and time consuming even when the images are put together incrementally. Re-setting the “baseline” snapshot to the current snapshot will require a reboot, though, and will take about 10 minutes or so.
  • Very small memory footprint: the Comodo Time Machine process and its system tray process combined take up less than 7 megs of memory.
  • Snapshot scheduling: you can schedule snapshots e.g. hourly, daily, weekly, monthly, or a one time event. You can also set it to take a snapshot on every system start (and even limit that to once a day if you like). This enables you to set scheduling one time and then essentially forget about the program, knowing you are protected.
  • Comodo Time Machine context menu synchronize optionSynchronizing files or folders: across snapshots, can be done via the right click context menu (simply right click on a file or folder and click “synchronize”) or via a search box in the program interface. You can overwrite the current files with files from stored snapshots or keep both versions.
  • You can set a rule for synchronizing files and folders: in other words, tell the program to always maintain the “new” versions of these files or folders even when moving back to a stored snapshot.
  • The boot up console: allows you to perform all sorts of operations, such as booting into different snapshots, while booting. It also means that you will always be able to boot into your system.

What I do NOT like about this program: some of these are “wish list” items, although I realize some points are necessary for the program to deliver what it promises.

  • Discrepancy between what Windows shows the free hard drive space to be, and the Comodo Time Machine free space: at one point Windows told me that I had 12 gigs free, while Comodo Time Machine had 0 space left and my system ground to a halt. This happened after I deleted a whole bunch of media files that were still preserved in the snapshot, and it was impossible to do anything except either delete snapshots or reset the baseline (and then reboot in either case). And although I could understand why this had come to be the case, it made me reconsider giving a blanket recommendation of this program to users who may not be tech savvy.
  • No way to compare and edit changes across snapshots: I would have loved at least to be able to see which files changed. Also, the option to permanently “let go” and delete some of these manually. The ability to filter out system files in such a comparison would be great as well. What I have found, in terms of file synchronization, is that it is typically impossible to remember all the files that have changed during the course of a couple of days of normal computer use, let alone a couple of weeks, making the synchronization function somewhat of a hit or miss affair.
  • Multiple boot systems: once you use this on your PC you cannot have a situation where you boot into multiple OS’s on that machine, unless you can install the program on all the different OS’s that you use on that particular machine (which limits you to Windows). If you boot into your machine via a USB or Live CD you are cautioned against writing anything to any partition.
  • The uninstaller is awful: on my Windows 7 64 bit, I got an error message mid-way through uninstalling that gave me quite a fright. There was no text, just an image of an exclamation point inside an inverse yellow triangle and an “OK” button. It left me wondering whether something had gone wrong and whether I will be able to boot back into my system at all (and kicking myself for not have a created an image of my hard drive before testing this app). It turned out that the blank error message should have read something like “you now need to reboot to continue uninstalling” and it went fine.
  • Excluding folders (or wish list item #1): I really wish I could exclude a folder or folders from being included in the snapshots. This way I could designate a folder for transient, gigantic media files that I do not care to have permanently fused into the snapshots. But I do think the likelihood of the developers allowing such a security loophole is probably zero.
  • Unclear on why or when some snapshots are performed: despite not having scheduled any snapshots in the scheduler or the settings, the system periodically made these on its own. While such snapshots are typically very useful I would have liked more clarity on when and why these took place.

The verdict: this program provides excellent security and is fairly easy to use; however, it may be suitable for some situations but not others, as outlined above. The bottom line is that if you have a good chunk of hard disk space that you do not typically use Comodo Time Machine may work really well for you.

What is impressive about this software is that it is able to do what it does seamlessly in the background and largely without user intervention. This is not the case when it runs out of hard drive space (you are forced to intervene then), but is true in general.

I like the ambition and scope of Comodo Time Machine. As a software tester I install all sorts of crap on my PC that I typically test and live with for a few days, and the possibility of an instant “undo” function that Comodo Time Machine promises sounds really good. Alas, it may be the case that my 12 free gigs on my hard drive are not enough (esp with my downloading large media files). That said, I am now considering upgrading my hard drive capacity, if only to take advantage of this excellent program.

Before you install this though, make sure you have a backup image of your hard drive (see the top of this posting, in red font, for some good freeware disk imaging options). If you are unclear on what a disk image is then stay away from this program.

Version Tested: 2.5.129464.157

Compatibility: Windows XP, Vista, and Windows 7. 32 and 64 bit support.

Go to the program home page to download the latest version (approx 20.3 megs).