Sometimes I just love application error messages :-). Today I decided to modify a web part on my local SharePoint site. So I loaded up SharePoint Designer 2010 and was presented with the “this website has been configured to disallow editing with sharepoint designer” message.
This message confused the hell out of me, as I was sure that I had used SharePoint Designer 2010 on this site before and as this was a local installation I would not have decided to remove the rights, but I thought I would double-check.
I found an excellent article on how to lock down SharePoint Designer, and after going through all the options I was able to verify that the rights were as I suspected and there should be no reason why SharePoint Designer was being denied access.
Finally I remembered that I had installed SharePoint Designer 2007 in order to do some client work and I wondered whether there was some sort of version conflict. In order to test this I repaired my SharePoint Designer 2010 instance, rebooted my laptop and suddenly I was able to open my site in SPD 2010.
So although I suspect that this issue is predominantly caused by the permission settings in SharePoint, it might be worth checking to see if you have the 2007 and 2010 versions of SharePoint Designer installed.
