Just had to completely rebuild Infostar VII. Everything appears to be working ok, however when users forward a mailbox message to another user and that users tries to access the message the system says "Please report Error Message 100 to your system Manager"
Can't find anything on this. Any help would be greatly appreciated.

check your Class of Service on the mailboxes, you will have various options there

I think the message was delivered and tagged, but the system can find it. might have bad sectors or software issues. sometimes the menu.btr or task.btr gets corrupted and might cause these issues. as brian said, check the class of service and recheck all of the programming. who rebuilt it for you?
is this a new hard drive?

May be a problem with your box stat file.
Copy the default file from zip directory to the working BTR directory. After you bring system back on line go the mailbox setup screen and resave all mailboxes to update the box stat screen. Believe this will correct your issue