I am having this problem too. I use Win98 + APACHE 1.3.12 + PHP4.03.
Warning: open(/tmp\sess_10c8913cd3f99c51567116935620fedf, O_RDWR) failed: m (2) in c:/apache/htdocs/session_test.php on line 5
I tried to change session.save_path in php.ini from /tmp to \tmp, then restart apache. But still got exact same error.
As for the two possible problems you mentioned, how do I know (1) if I got corrupted vars, or (2) the dir permission is correct? Should I specify the tmp dir as something like: c:\apache\htdocs\tmp?
Thank you all for help.
Ron