Just follow this blog and I found way to figure out the access denied erros in SharePoint 2007.

First, if the error url look like

http://%5BServerName%5D/_layouts/AccessDenied.aspx?Source=%5BAnyUrl%5D &Type=list&name=%7B12151589%2D7A0B%2D40EE%2DBD92%2DADB851B3D78E%7D

That’s means you don’t have permission to access one list whose GUID is
. Then go to List Edit page and replace the GUID with this one so you will know which list give permission error.

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