Hey, I've got a problem that I've been trying for days to solve, with no luck. I'm attempting to install Visual Studio 2005 Pro on Windows Vista Ultimate x86. Every time I do, though, it copies all the files, adds all the registry entries, and then craps out with the following error: Error 1935.An error occurred during the installation of assembly 'Microsoft.VC80.DebugCRT,type="win32",version="8.0.50727.42",publicKeyToken="1fc8b3b9a1e18e3b",processorArchitecture="x86"'. Please refer to Help and Support for more information. HRESULT: 0x800736FD. I've completely shut down all virus scanner related processes and services, I've uninstalled and reinstalled the .NET 2.0 Framework, nothing works. I Google for the HRESULT code, and get absolutely nothing. Like, literally, nothing. It's as if that HRESULT code doesn't exist. I tried a few common solutions about error 1935 that I found. One of these was deleting all the existing *.VC80.* folders in the %windir%\Winsxs folder. I did that, and the error message changed. Or rather, it was the same error, same HRESULT code, but it complained about a different assembly: Microsoft.VC80.ATL, which was one of the ones I deleted. I replaced the files back into the folder, and the message changed back. So it seems to be only complaining about assemblies which are not already there. It seems to me, that it's unable to register new .NET assemblies into the GAC. If anyone has some hints or ideas about how to track this error down, I would greatly appreciate it. I've been pulling my hair out for days now.