SharePoint Crawl Log Error: “The SharePoint item being crawled returned an error when attempting to download the item” .. for eg. *.aspx files
After some research I found a solution for that problem
Open Regedit on your search server/s
Navigate to this registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office Server\14.0\Search\Global\Gathering Manager
Change Value "UserAgent" from "MSIE 4.01" to "MSIE 8.0"
Restart the SharePoint Search Service.
Open a SharePoint PowerShell
Get-SPSessionStateService
If this returns false then we need to deploy one
Enable-SPSessionStateService -DatabaseName “NameOfDatabase”