Outlook won't remember addresses

[canooten]

I've always been used to Outlook (any version....I use XP) remembering email addresses I've used in the past. Even if the address wasn't in my contacts list, the program kept a list of all addresses used and would automatically fill in the rest of the address. Recently it has stopped doing that unless I've previously used the address that day (or since opening the program).

I know there's a setting in the advanced options for turning off suggestions and auto complete, but these are checked as on and they don't seem to be working.

Anything else I can try?