non-member image upload problem

[jimraynor]

when visitors try to upload image in member.php?action=uploadform.

this error happened and system auto-redirect login.php page:
You have specified an invalid username or password.

My category permission is available for visitors upload.

Upload permission: ALL


i searched and finded this thread
http://www.4homepages.de/forum/index.php?topic=13439.0

but i cant find these codes in index.php?


how can i fix this?

[jimraynor]

Somebody help me please my visitors cannot upload image my gallery in member.php?action=uploadform