Database Corruption

Good day all -- We are running 7024 with MySQL native and had problems where you get the prompt at login to run the database repair. I ran the repair and noticed we were still having some problems that included: Can't sort systems, can't add a name to a system and we had doubled the count of our servers. It appeared we had a seperate entry for an IP address and an entry for a name for each server. I ran the repairdb again and this time received the following error:
myisamchk: MyISAM file ..\mysql\data\OpManagerDB\polleddata.MYI
myisamchk: error: 13 when fixing table
MyISAM-table '..\mysql\data\OpManagerDB\polleddata.MYI' is not fixed because of errors
Try fixing it by using the --safe-recover (-o) or the --force (-f) option

I've included a screen capture of the output.

What causes this and how do I fix it? Thanks.