Are you using source control? i.e. Git

Yes Kevin I am using Git.

You've probably already checked, but any changes recently? Or are there unstaged changes?

Guessing it's a single character giving you an issue in one of the files.

No there are no unstaged changes:(

You might wanna remove all sensitive info from the web.config/umbracosettings.config and run them through some XML validators. If that doesn't work, I got nothing :)

Ok, one more thing. Before the above mentioned error occurred I used

        var ms = Services.MemberService;
        ms.DeleteMembersOfType(1045); 

to delete all the members of a specific type.

After that following using statement

        using umbraco.presentation.cache;

in my SurfaceController started giving "Cannot resolve symbol cache" error.

Shot in the dark: check to ensure your applications.config and trees.config didn't get emptied.

Kevin I validated both config files and there were no errors:(

So as a lost resort I cloned the project from the main repository, build and the website started to work :)

I then compared all the config files in working and non working versions but they are identical so I have no Idea what was the problem but atleast its working now. Git is good;)

The project version(which stopped working) was in my DropBox actually. In the bin folder I found some conflicted copies of the dlls. I replaced all the dlls in the not working version with the dlls in the the bin folder(the newly cloned/working version from the main repository). Things started working :)

So was it my dropbox which screwed things up for me :) ?

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