Had a problem with my test system recently – I was doing some maintenance on one of my Active Directory servers and noticed that it had SharePoint installed on it. So in a bid to keep a test environment relatively clean, I uninstalled the SharePoint instance on that server.
A few weeks later (tonight actually) I needed to do some tests around how SharePoint renders "Limited Access" groups… so I load the URL and get the following message:
Please hit the "Refresh" button in your web browser to retry your request. … Failed to initialize the AppDomainLM/W3SVC/1/ROOT/
Exception: System.IO.FileLoadException Message: Could not load file or assembly ‘System. … or one of its dependencies. Access is denied.
That’s funny – it was working last time I opened it! The web sites are still running, no service account lock-out, security seems to be a bit odd though… the sharepoint app folders on the hard dive all seem to have some broken accounts associated with them. That’s when the penny began the long fall down… because I have 2 DC’s for the same domain, when you install SharePoint on a DC it creates the WSS_WPG and WSS_ADMIN_WPG groups which have special permissions – service accounts belong to them, etc… but installing it on a DC creates them as an Active Directory Group – so installing them is fine, but when you uninstall one of the instances on one of the servers, it removes the groups from the Domain, rendering the other instance useless.
Not the end of the world though – uninstall and reinstall SharePoint and attach to the Admin database – bam, all the sites reappear (as do the AD Security groups).