I've got a single server install of Sharepoint 2010 enterprise with SQL 2008 both installed. The site has been running fine until I got a complaint from one of my SP managers that she was getting Access Denied errors when she tried to upload a document, then I got another one. At this time I tried it myself and I've got the same problem. BTW we can use explorer view and upload documents without any issues. After continuing to troubleshoot, I found additional links that are also broken. They are:
1. The help button also give me the same error
2. On the site, Site Collection, Site Collection Administration, Search Keywords, give me the access denied error.
3. In Central Admin, Security, configured managed accounts, I get the following message:
The given key was not present in the dictionary.
Troubleshoot issues with Microsoft SharePoint Foundation.
Correlation ID: 78454743-6409-4d79-9a30-94
Attached is a much cleaned up log file. It contains the error messages when received as I tried to utilize the above controls. This log was taken with logging set to verbose.
This issue was posted at the following link, but no one wants to take it on.