session_start() ps_files_cleanup_dir:

How are you. I am getting this error, but the strange thing is that it appears sometimes.

PHP Notice: session_start() [function.session-start]: ps_files_cleanup_dir: opendir(C:\WINDOWS\Temp) failed: No such file or directory (2) in C:\Inetpub\wwwroot\reztimeout\default.php on line 2

I am running IIS and SQL Server 2000(PHP 5.
How can I fix this? Anyone.