Drive Image - Disk mgr?

I get the following message when trying to run Drive Image:

"Error 91 Disk Manager has been detected on drive %lu

If you no longer need to use Disk Manager on your hard drive, you can fix Error 91 by removing the Disk Manager signature from the Master Boot Record (MBR)."

I have 5 partitions running XP & ME.

What is Disk Manager and do I need it to run dual OS's?

Disk Manager (by Ontrack) was used last century (!) to make larger Harddisks (either over 8.4 or over 32 GB) fit into PCs with a limited HD-capacity as recognized in their old BIOSes.
If your current BIOS recognizes large-sized HDs, then you can remove that signature from the MBR.
It has nothing to do with running multiple OSes.