How rename a file?

I use next code:

Rename $EXEDIR\oQ9EmzAs.xml $EXEDIR\1234567890101111.xml

Bun it's dont work. it's work only if destination file will have less or 8 symbols.

Sample:

Rename $EXEDIR\oQ9EmzAs.xml $EXEDIR\12345678.xml - It's code work.

How rename file more the 8 symbols in name?

Plz, delete this topic.
All work.