Did you happen to register the SDE_COMPRESS_LOG file with the geodatabase? Try the following:
1. Rename the SDE_COMPRESS_LOG file using the Catalog window to SDE_COMPRESS_LOG_1
2. Execute the compress again
This should recreate a new SDE_COMPRESS_LOG file.
I would recommend deleting the log file, as it keeps track of each database compress. But, if you were to delete it, it would be recreated after your next compress.
Take a look at the following link. It has a description of each system table for the geodatabase.