vBulletin Manual - Move Profile Pictures to a Different Directory

Selecting the Move Profile Pictures to a Different Directory option will display the current storage location for your avatars and allow you to change it.

Profile Picture Path - enter the new location where the avatars will be stored on you webserver. This is the path to the directory where you images will be store. This should be both readable and writeable by your webserver and relative to your forums root directory
URL to Profile Pictures - enter the new url of where the avatars will be stored. This should be relative to your forums home page

Once the new location details have been entered click the 'Go' button.

The settings for the new location of the profile pictures will have been updated.

Note:

You must now manually move all profile picturesto the new folder, using an FTP client or a shell command such as:

mv -rf ./customprofilepics/* ./profpictmp/