Problems with updating GroupWise 4.1a

I have GroupWise 4.1a.
I have installed UK ja Finnish (SU) versions but i am not
sure which versions i have of them.
There are ofsu0019.ver and ofuk0024.ver files in my domain
directory. UK-files are from 7.5.96 and finnish files
from 24.4.95.
When i try to update finnish versions with GWSUC3.EXE
i get the following error message and upadate aborts:

****
  Warning wpt0036: Old File not found.
  However, a file of the same name was
  found.
  No update done since file contents do not match.
"This comes about 5 times"
   Warning wpt0015: Old File does not exist
A warning or error occurred while attempting to patch files.
The patch will be aborted and original files will be
preserved.  Please examine the PATCH.ERR file in the
domain\WPOFFICE\OFWIN40 directory for an explanation
of the patch error encountered.  Correct the problem and
retry the patch.

The PATCH.ERR file is as follows:

ENTRY: NTWIN.EXE
  Warning wpt0036: Old File not found.
  However, a file of the same name was found.
  No update done since file contents do not match.
ENTRY: OFWINENG.DLL
  Warning wpt0036: Old File not found.
  However, a file of the same name was found.
  No update done since file contents do not match.
ENTRY: OFWINFIL.EXE
  Warning wpt0036: Old File not found.
  However, a file of the same name was found.
  No update done since file contents do not match.
ENTRY: VEWINFIL.EXE
  Warning wpt0036: Old File not found.
  However, a file of the same name was found.
  No update done since file contents do not match.
ENTRY: WPDE20SU.DLL
  Warning wpt0015: Old File does not exist

First 4 files are in my C:\OFWIN40 directory,
but i can't find WPDE20SU.DLL anywhere ???

Is that the problem ?