.Net Framework issues on Windows 7 (probably after a gone-wrong SP1 update?) - Event Viewer won't work, nor Zune

Question

I'm having problems running Event Viewer (wherever I open it, a "unable to create snap-in" error pops-up, the error details something as CLSID: FX:{b05566ad-fe9c-4363-be05-7a4cbb7cb510}) and other applications, such as Zune (fails to open everytime, since right after the installation) or Visual Studio (had to install it and remove it a few times, had an issue with AddInUtil.exe if I recall correctly).

I think I figured there is a common cause, which is .Net Framework, which somehow screwed up. It could have happened when I last tried to update Windows7 to SP1, the update failed and the system would lock to a black screen as soon as I would turn on my notebook. I fixed it using System Restore (tried again another time, got the same mistake).

Some more information:

• I'm pretty sure my system is clean, I scanned it twice with avast (full and in-depth scan, of course), tried to reinstall it just in case, made a boot scan.. so here should be no things such as malwares, viruses, trojan horses..
• I already tried sfc /scannow, I think it fixed some things but if I launch it again it says there are no problems to fix
• I know the Event Viewer issue is sometimes connected to a mmc.exe.config calling a wrong .Net Framework installation, but there is no such thing on my system
• I tried going on "Turn Windows features on or off" in Control Panel, .Net Framework is an half-checked square (the square is full, there is no check on it). If I try to enable all the features and confirm, it will stay idle for a while, then an fault error window pops-up, saying it was unable to turn some features on and prompts me to reboot. After the reboot nothing changes, the square is still half-checked.
• I also tried running the .NET Framework verification tool: it turns out there actually are some issues in my .NET Framework 2.0 and 3.5 installations ("Product verification failed"). The only errors I can find in the logs are some missing .nlp files (such as big5.nlp, normnfc.nlp, normnfd.nlp, prcp.nlp, sortkey.nlp, xjis.nlp)

Anyone got an idea? As you can see I tried pretty much everything.. Apart from the program issues the system works just fine, but it sucks to be without Event Viewer (it's one big useful thing) and I need Zune for some things, so I'm getting pretty tired of the situation (but I wanted to see if there is a way to fix this without reinstalling the whole system!)

Answer 1

Use the System File Checker tool (SFC.exe) to determine which file is causing the issue, and then replace the file. To do this, follow these steps:

1. Open an elevated command prompt.

   • Start → All Programs → Accessories

   • right-click on Command Prompt, and then click "Run as administrator"

   If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.

2. Type the following command and press Enter

   sfc/scannow
   

   This command scans all protected system files and replaces incorrect versions with correct Microsoft versions.

More info about the System File Checker in this Microsoft KB article.

Answer 2

You can uninstall the various versions of the .NET Framework from the Control Panel, like any other program. Then download and install the most current version from http://www.microsoft.com/net/download. If that doesn't fix the problems, then the .NET Framework is probably not the issue.

Answer 3

Just to give a few clarifications to previous comments. Applications dont automatically roll forward to .NET 4.0 from .NET 3.5 so if you have something that depends on .NET 3.5, you need it installed or you need to add an application config file to the application that will tell it to run on .NET 4. Also, you wont find an installer for .NET 3.5 on Windows 7 because its built into the operating system.

The guid you mentioned in your error FX:{b05566ad-fe9c-4363-be05-7a4cbb7cb510} corresponds to eventviewer.dll so it makes sense you are seeing that when launching event viewer.

What would probably be handy is to run procmon on the machine and capture all the output for the process to see what exactly is happening at the time of the failure.

If you want to email me the procmon trace, I can try to take a look at it.