Outlook errors

Can someone tell me what the problem might be?

error messages:
1st message:
Personal Folders : This information service has not been configured. Select an
existing file to configure or type the name of a new file to create. I hit OK
and I getthis second screen:Create/Open Personal File folders
look into Outlook and then an icon with an archived file
The third messge is Personal Folders again only this time it says: Properties
for this information service must be defined prior to use.These errors
messages all started happening after I lost my Z.Sent Items a week or so ago so
I think it is related. I have left the errors on my screen. I reboot to get rid
of the errors but they keep coming back on a regular basis.