If you have this database (0.07991) to (0.0801) issue with upgrade as I had:
>> checking version of existing database
>> FAILED
>> could not get propper db-version table entry. Please view
>> Installation Guide on hints how to proceed.
this helped:
To fix this issue please leave only one row in {table prefix}_db table in your database and run upgrade process again.
I had same problem because I had two rows in this table. After I have deleted one upgraded process completed successfully.
see
http://www.streber-pm.org/5952 for reference
I still had to do this afterwards:
Go into file:std/common.inc.php and remove from line 97 :echo "%% strip slashes"; - that is all. :: See
http://www.streber-pm.org/5870 for reference
Now all works fine :-)