Iphone

Microsoft Outlook 2003 is returning "The messaging interface has returned an unknown error" anytime that I try to do anything including create new mail. If I try to look at my E-mail account, I get a message "The operation failed due to a registry or installation problem." I have done uninstalled and re-installed Outlook 2003 and have tried to delete the profile in the registry and recreate with a new installation. In both instances I get the same errors. This happened when setting up a new computer and moving the .pst files from the old computer.

Iphone

You may have created a new Personal folder and made that the default. You can go to File > Data File Management and select which Personal Folder (PST file) should be the default.

To consolidate the two personal folders, move the emails and contacts to the default folder. Once you tested everything to make sure emails are going to the desired folder, then you right click the other folder and select Close.