SharePoint 2007 File Not Found Problem

Many People faced File Not Found Problem When they deployed SharePoint 2007 Site. When I investigated this problem found many common reasons.

1. Declare physical folder with same name with sharepoint virtual folders.
2. Missing deploying physical files features, delegate controls, user controls, etc.
3. Didn't give a physical files suitable permissions.
4. Missing deploying custom templates.
5. Didn't publish content files masterpages, layouts, pages, stylesheets.
   Note: To discover this problem:
   a. Change Master page from sitesettings to standard masterpage
   b. If same error already exists republish layout.[checkout, checkin, publish layout]
   c. If same error already exists validate existing physical controls, refrence dlls.
   d. If error doesn't exists when you changed master page use your masterpage do same b,c with master page.
   
6. Didn't deploy dependence files or sdks (refrence files of your dlls)