You may receive the error "BC30138: Unable to create temp file in path 'C:\Windows\TEMP\:' Access is denied" while trying to debug or browse your ASP.NET Applications.
This may occur if the ASPNET account doesnt have sufficient priveleges on the 'C:\WINDOWS\TEMP' folder, in windows versions prior to Windows Server 2003.
In Windows Server 2003, it is the Network Service account that needs to have the necessary rights for that folder.
Even if you assign rights for EVERYONE it wont work since these accounts do not form a part of the EVERYONE account.
The error can be resolved by explicitly assigning MODIFY rights to ASPNET User account (prior to Windows Server 2003) and NETWORK SERVICE account in case of Windows Server 2003.
That should solve the problem.
Cheers and Happy Programming !!!