Access is denied. Verify that either the Default Content Access
Account has access to this repository, or add a crawl rule to crawl this
repository. If the repository being crawled is a SharePoint repository, verify
that the account you are using has “Full Read” permissions on the SharePoint Web
Application being crawled.

Solution Tried,

1. Go to command window and type regedit.exe
2. Once opened the registry editor, just navigate to “HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3. Right click on “Lsa” and create a new 32bit DWORD value
4. Rename it as “DisableLoopbackCheck” (Note: you cannot rename it actually. so, once created the DWORD value, directly paste/type as “DisableLoopbackCheck”.
5. Then again modify the value of “DisableLoopbackCheck” as “1”
6. Close the registry editor.
7. Now start to crawl the content.