Symptom

The version file can not be read. Opening the version file failed with:
"File ...: No valid PTV binary format ID."

Cause

Possibly the wrong file was chosen to be read. Or unfortunately this version file is defective, it consists only of a binary fragment without header.
The header must hold the string "PTVSYSTEM" otherwise an error message is returned.
Has it been saved to an erroneous data volume, like an USB stick or a CD/DVD?

Resolution

- Check that really a Visum version file was chosen.

- Check that the matching Release version was chosen.
Version file can be opened with powerful editors like Textpad or use the application "Lister" executed with F3 in Total Commander.
The first two lines should hold a string like:
"PTVSYSTEM   VISUM       Version             Vers. 23.01-5"
The "vers." indicates the Release version used to write the file. 

- Check the binary code and compare its end to that of other Version files. The file could be incomplete or shortened.

- Check USB sticks or network connections for technical issues. 

- Use a backup file.