First – don’t panic – I realize you have no information when you get this error and you have no troubleshooting direction at all, but don’t panic. Help is on the way.
Follow these three easy steps:
You should now be well on your way to troubleshooting your problem. In SharePoint, if not – go to the SharePoint root:
(C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14 \TEMPLATE\LAYOUTS\web.config)
Change Custom errors mode to “Off”, in the web.config file there.
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