I started a Full Crawl of Content DataSource and I get this error message:
"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
even if I use an account with Full Read permission on that Web Application.
I go on Search Server machine for Sharepoint farm, with credential used for Default Content Access Account, and I try to navigate to site collection in that Web Application: I get error "Access Denied", browser asks me for credential and then "Error 401"..
So, the problem was that account used for Default Content Access cannot browse to site collections in Web Application, from the server search.
I correct with this post, from Microsoft: "You receive error 401.1 when you browse a Web site that uses Integrated Authentication..."
I followed Method 1 and works for me, very well!
Note: you can use method 2, but you have to restart computer, but method 1, you can restart only iis services..
Then, I go on Central Administration and Search Application Service, restart Full Crawl and.. it's all ok!