As an update to this ongoing issue, even though this thread is old, the issue is still striking PCs everywhere!
My problem began when I attempted to install the SP1 for Visual Studio 2010. Unlike a previous poster, I am not able to simply remove the .NET framework installations for any version as I develop applications utilizing this framework. However, the installation hung from Windows Update... and I've been having issues ever since.
System:
Toshiba Satellite P750 Laptop (just purchased 3 months or so ago).
Windows 7 Home Premium
Symptoms:
1. After a fresh login, Windows notifies me that it has discovered a problem with Visual C++ 2008 redistributable installation and asks me if I want to repair it. Repairing it directly in this manner fails every time, so I had to download an install from Microsoft to get it to install properly.
2. Only a handful of applications fail with the error code 0xc0000006; unfortunately this includes my Anti-virus program!
3. My system reacts extremely slow at times (especially when attempting to open a browser), but the windows will eventually come up. Unless it's on the list of applications that just straight out fail opening with this error. I use a system resource monitor, and despite how slow my system is reacting to actions I request of it, the system is showing I'm using no more than 30% of my RAM at any given time, and the highest any of my four processing cores is ever utilizing at any given time is no more than 5% of each's resources.
Steps I've Taken:
1. Performed a system restore to the point before I installed VS 2010 (let alone the SP1 update that seemed to spur this entire problem). This did not fix the problem.
2. Download the 2008 redistributable from Microsoft, reinstalled the library. This succeeded without issues.
3. I've read that running an elevated command prompt (admin), and running the command sfc /scannow may help in resolving the matter. I ran it, and it said it succeeded without issues (unlike what others have reported after attempting this step), but my scan reported that it found no integrity violations. However, this scan once complete seemed to speed my system back up to the point that my browsers and other such working applications aren't slowing me down any longer. My anti-virus and other non-working applications continue to provide the 0xc0000006 error.
This is where I am stuck, but I figured my progress may help someone else having this issue. I have way too much data to be capable of backing everything up for a fresh install, so I am attempting to do this without the need to order a very large backup storage device for merely taking care of this matter by erasing the issue entirely. Though I will say that I probably will end up buying something (it would be my own fault if I don't ... really should be backing things up! lol).
Hope this helps someone else! I know I can't be the only dependent (in some manners) with the .NET framework.
[EDIT]
After running a registry scan, and finding a horrific number of inconsistencies that needed to be repaired, the system ran faster for a short bit then started up again. I attempted to manually start my security services to see if that would help to resolve the matter, but the services would not run. I tried to uninstall the security program (AVG Internet Security specifically), the uninstall failed no matter how I tried to do it. I attempted an AVG repair via a downloaded install file, that failed when it got to the point of attempting to start the services. I downloaded the AVG remover tool, and this cleaned my system. As part of the process, it required a restart partially through the removal and as such I discovered that despite me reinstall the Visual C++ 2008 redist (successfully based on what the install reported), I still had the corrupted library issue. This was pointing directly to msvcr90.dll; so I went on my way of removing the MSVC++ 2008 redist, version by version (I had a few, and I started with the most current version working my way down to the oldest), using Add/Remove Programs in Control Panel. I then re-ran the MSVC++ 2008 redist, and it stated it installed correctly. I don't trust Microsoft, so I restarted my computer. Luckily for me, this install worked, the problem was resolved and now I am in the process of reinstalling AVG and other programs (I did remove the other programs that were failing to start with the same error message). If I don't come back to edit this post another time, this has fully resolved my problems.
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