Can not export mesh as .unv format (Salome 9.9 Win)

Hi, Dear Salome users!

I have a trouble, when exporting any mesh in .unv format. Literally any mesh, even realy simple one. Every time I try to do so, I se the following message (attached image).
I tried both Salome 9.9 and 9.7 on Windows. Could you please suggest me anything to solve it?
Thanking you in anticipation.
mesh_error

I did not manage to reproduce the reported issue with SALOME 9.9.0 on Windows. I managed to mesh and export to UNV file format a box). Can you give additional informations like file name, directory path, installation directory, Windows OS version (in a cmd terminal type winver)?
In addition, is it the only format for which an error is triggered ?
Regards.