I came across a "File Not Found" error when attempting at access a SharePoint Page that had a custom Web Part. Not a very useful error message to say the least. So, in order to actually get more information you will need to have access to the Web.Config file.

Follow these steps:

  1. Navigate Here:
    "C:\inetpub\wwroot\wss\Virtual Directories\<your web app's virtual directory>"
    1. You can also open IIS
    2. Expand Sites.
    3. Right click on your SharePoint site
    4. Choose explore.
  2. Copy and paste the web.config file (making a backup)
  3. Open web.config using in your favourite editor.
  4. Search for “CallStack” , set this equal to true
  5. Search for “Custom”, set the customerrors = “Off”
  6. Search for “Debug”, set Debug = “True”
  7. Save the web.config file and refresh your page in the browser


You should now see the problem in the Call Stack and have enough information to know what the problem is or could be.

When you have fixed the problem you may need to so a iisreset to see the site again. Finally, you will need to revert all of those changes to the Web.Config file so that the user doesn't see "Too Much Info"!