If you've ever got an error along the lines of
Some of the properties associated with the solution could not be read
from Visual Studio (in my case 2008), it could be due to duplicate entries in the solution file for the global section for source control.
I found a related answer to this here, except that I'm using SVN for my source control, with the PushOK plugin, instead of TFS. After manually scanning the solution file, I noticed that the source control section that more or less matched that in the article was named "SourceCodeControl". Searching for GlobalSection(SourceCodeControl) = preSolution returned two results; I deleted the last one in my solution file (it had 1 less project in it) and the error message stopped appearing.