As previous posts point out the PM00400 keys master file can be the source of several errors. MS does not recommend to delete the PM00400 file and recreate it. They now recommend that you run check-links. I have found that check-links will not correct these errors.
A previous post outlined a method to do this manually. However, a client of mine was kind enough to provide me with a script that automates this entire process or recreating the PM00400 table.
I will post the SQL script here as soon as I can. In the meantime if you need it sooner please contact me via email.
**Update**
This script will recreate the PM00400 file. Make sure to do a full database backup and have everyone log out of Microsoft Great Plains. If you have any problems downloading the file, please let us know.