The Vendor ID that was automatically created already exists in Sage 50. Manually enter another Vendor ID when trying to save a new vendor or maintenance record.
Your data files are damaged and need to be repaired. We have found this to happen in Peachtree Accounting Version 2007 and higher. We would assume it could happen with Customers, Inventory or any type of Maintenance Records.
The file has a damage record pointer and cannot be fixed using Data Verification or Reindexing.