If a compressed record in the data file had a corrupted length, or corrupted data, and decompressing the record caused the record size to grow beyond 4K then both DBCHECK and the database manager would fail catastrophically when trying to read this record. In 32-bit windows environments a GPF occurred, resulting in failure of the DP4 service. On MS-DOS a complete hang of the machine resulted.
The code to decompress data has been updated to make sure that no more than 4K of data is decompressed. In addition the database manager now checks the record length is exactly what it should be. In previous releases the record length was only checked for being a possible record length, not the correct one for the table being read. This should make it harder to miss corruptions in the data file.
Where the version affected is given as 4.5xx or 4.6xx, all versions of DP4 issued prior to the date of the fix are potentially affected. Where a specific version number is given the problem was introduced by that release and prior releases are unaffected. If a patch release number is also specified (in parentheses) , the fault was introduced at that specific patch level.
Due to limitations on available web space downloadable fixes are only available for the most commonly used environments, and may not be separately available in both 4.5xx and 4.6xx flavours. If a file you require is not available you can ask us to e-mail it to you.