I run Outlook 2003 on Windows 7 Pro 64-bit. Two problems there right now.
Problem 1, happened for weeks, minor impact: OUTLOOK.EXE - System Error "The program can't start because BCSRuntime.dll is missing from your computer. Try reinstalling the program to fix this problem." (This problem is mentioned too in case any relevancy to the following problem).
Probelm 2, just happened but severe: I can start Outlook and see Mail, Calendar, Contacts, Tasks and Notes. But I cannot add anything by clicking New. It said "The messaging interface has returned an unknown error. If the problem persists, restart Outlook."
Initially I thought it was the newly installed Outlook Connector problem. I tried
1. Help>Detect and Repair...
2. Windows Update
3. Select Repair from the Office Professional Editional 2003 CD
None of the above works!
Then I guess it could be the .pst file problem. So, I wish to make a backup of it, and from Start > Control Panel > Mail > (select the profile) > click Properties > Data Files...
Here, nothing happened if I chose the profile in use. But when I chose another older profile > click Properties > Data Files..., I can see and open it.
Then I went to the folder (storing both .pst files). Both can be seen.
Any advice to fix this problem?