Something strange happened on my local laptop: my web site that worked locally for a long isn't launched...
Trying to localize the problem I've created a simple web site with 'index.html' file only. It works fine under ASP.NET 2.0, but when I switched App Pool to use 4.0 - it stopped to work.
When I open web site in browser it shows the following error:
HTTP Error 503. The service is unavailable.
The worker process failed to initialize correctly and therefore could not be started. The data is the error.
I've reinstalled .NET 64 - that helped.
It seems like either some files in "C:/windows/Microsoft.net/Framework64/v4.0.30319/" folder or I removed them myself (VS sometimes complains on files in "ASP.NET Temporary files" and their deletion helps)... Probably I didn't pay attention that those folder not a temporary...
In this case, why VS complained on files in "C:/windows/Microsoft.net/Framework64/v4.0.30319/" folder... ok, now it's hard to say.