REVO uninstaller. IMPORTANT and dangerous flaw

This topic was published in 2010, so Comodo Forum suggested I start a new thread. The reason is that I had precisely the same problem as described below. The problem appeared when I was using Revo for uninstalling a major program (Libre Office.). Revo had worked fine before, but now the result was catastrophic. The computer became unusable in the same way as described below, with the difference that even with the WinOS DVD it was a lottery if it would start - most often the response was that the system was shut down to protect it.

I have no rogue programs and the computer was stable and unproblematic until I did this uninstall operation. After uninstalling Revo, and repairing the OS it seems to have recovered, but this took several hours to fix.

I am reproducing this info below, because it was well and systematically written including that the problem was exactly reproduced when using Revo again after reinstallng the OS.

I have Win OS 7 ultimate which has worked perfectly until this accident occurred.

If you use Revo, do read this (sorry lost the link, will try to find it again):


Posted by:
Comodo’s Hero
Posts: 342

Revo Uninstaller and the dangerous flaw
« on: August 27, 2010, 02:10:50 AM »

Well, Revo did help me remove a couple of traces of rogue programs so I guess I’ll take it as a pseudo-security product.

So what’s the danger? Well, Revo Uninstaller has been my personal favorite since I first discovered it. And I have been using it for a year now. Since then, I have had no trouble with it at all. Until that faithful day…

Log file handwritten. Started logging after printer stopped working. Original file on notepad. Notepad crashes at one point. Have to write log instead.

2:53 PM August 21, 2010, Saturday. The printer stopped working. Tried to trace what caused the problem.

4:52 PM same date. Could not trace problem. System restore did not fix problem. Backup did not fix problem. Printer still not functioning properly.

8:23 PM same date. Tried reinstallation. Uninstalling with Revo

8:31 PM same date. Restarted PC, stuck on startup splash screen.

8:33 PM same date. PC is nearly unusable. Network no longer functional. Cannot run programs via explorer. Worked around via Run function. Applications crash a few moments after launching.

8:45 PM same date. Restored from Revo. No longer stuck at splash screen. Applications crashing. Printer error. Hardware error. Cannot capture screenshot.

9:27 PM same date. Cannot trace. Applications crash even in safe mode. Nothing else to restore.

August 23,2010. 7:43 PM. Will try to fix with reinstallation of printer.

8:05 PM. still no luck. preparing to reinstall OS.

10:40 PM finished installing OS and drivers.

11:34 PM installed all needed software. Running on basic mode. Did not install printer. Now using revo portable. reluctant to install.

4:30 AM August 24, 2010. will try to reproduce problem. installing printer. HP

4:46 AM finished installing. uninstalling via Revo uninstaller. Program traced. No other application running except advanced task manager. Checking for other processes. Non-detected. No internet connection.

4:52 AM. Problem reproduced! Stuck at splash screen. Cannot connect to internet. Proceeding to reinstall OS.

Any insight? Should I keep Revo?


I remember that the Libre Office uninstall did not work completely. There was some error so it was interrupted towards the end of the uninstall. This occurred when the Liibre Office uninstall ran, not when Revo did the additional fiel and folder deletes.

Therefore, I first suspected Libre Office uninstaller to be the culprit. As there were remnants left and I did not dare to run Revo again, I reinstalled Libre Office and ran its own uninstaller. This time it worked fine.

Could it be that at times, when the programs own uninstaller does not work properly, that Revo gets involved and causes some critical system file delete?

Hi Estonijaan,
The lost is found. :wink:

Revo can dig deep, caution is required with these types of uninstallers.

Revo uninstaller isn’t a security product… I’m moving this post to the General forum.

(Not to mention that any concerns regarding Revo should be brought up with the developer, not here. Yes, I realize the original thread is two years old, but the statement still applies.)

When Uninstalling certain Programs with REVO there can be unexpected and serious problems. The reason is that some Programs when they Install and you give full permissions, will alter System .dll files and rewrite them or replace them with altered .dll’s which are used to help run the new Program.

You decide to Uninstall the Program and select Level 4 in REVO, to remove every single trace of the Program. That’s where the problem comes in. REVO does precisely what it claims to do, and exactly what it is very good at doing: it completely deletes every file related to the Program. However, the Program has already altered crucial System files: plus renaming them as their own Program .dll files. When REVO uninstalls all ‘Program files’ the computer is left damaged with incomplete System Programming, with critical System .dll files [that were renamed] now removed!

In short, it isn’t REVO’s fault at all, and isn’t any kind of flaw in their Uninstaller Program in any way. It is in fact the programmer’s fault who originally built the Program being Uninstalled, who altered critical System .dll’s including renaming them. That’s done for one of two reasons, one of which is for runnning some aspect of the the program. The other reason I won’t mention because it offends the sensibilities of some to suggest it, but the renaming of those .dll’s gives a big hint.

Per the above, I am only referring to a failure following the use of REVO to Uninstall. If on the other hand REVO is malfunctioning and rendering a computer useless just out of the blue, without having used it to Uninstall something, then that’s a horse of a different color.

I couldn’t tell from the first post if they were saying there was first a printer failure, then serious problems started only after attempting to Uninstall printer with REVO? The particular printer company mentioned, to my experience, has a reputation for just this kind of alteration of System .dll’s for their own reasons, related to various control of computers.

Their printers can be quite difficult to fully and completely uninstall without something like REVO. You’d have to be skilled enough to go in and change the Registry, finding all the altered System .dll’s and rewrite them to original code and rename them by original name again. Otherwise it can also be dangerous to attempt REVO Level 4 Uninstall for the same reasons.

HP is fully aware of this scenario and willfully chooses to continue to write their Printer Installation Programs this way for whatever reason. Due to their alterations to programming as described, and their huge and demanding load on the File System, plus their collection of Computer Data I have no use whatsoever for any of their products. It’s not REVO’s fault there!