The main antivirus base is called AVPyymm. You'll see the exact file list and can cross-check that you have not forgotten to copy any of the antivirus databases. When a new cumulative update is released then you have to replace the complete database set on both Diskette 3 and 4 again. OLE documents have corrupted internal structure. Archives have corrupted internal structure.
Some viruses require multiple records, for others a few records cover for thousands of variants.
AVP's anti-virus bases are usually updated on a daily basis. If you don't want to miss any updates, make sure, you subscribe to the AVP info mailing list or check our AVP News section on a regular basis. And no, you do not have to pay for anti-virus base updates as long as you retrieve them via the Internet and as long as you are holding a valid and current license. I can't update, the download aborted or not all files where transferred. First, verify the pre-configured download address AVP Updater uses to download the updates from.