You are doing a big misunderstanding.
The advise to DoiOkiBlu is useful for the user of shared server which limits user's access authority by open_basedir.

If you add only /tmp/ into open_basedir, you'll be able to access to only files under /tmp.

The best setting of "open_basedir" is blank.

Quote:I can't see your environments and settings.
Show your result of 'Module check'.

Quote:Usually unix servers uses /tmp as upload temporary.
What do you means about 'few days ago'?
If you updated 2.05 to 2.50beta, it may be a bug.

Anyway, tell me your environments and settings.