Got an error while opening MS PowerPoint presentation

Hi,
I recently upgraded MS Office to a newer version in my Mac PC.
I tried opening a presentation, but then I got this error message.

Error:
PowerPoint cannot open the file /User /geeteshbajaj/Desktop/Themetest/New Theme Edited.thmx.
The file may be damaged, or it may have been created in a pre-release version of Power Point.
I then searched for the file that was indicated in the error message, but couldn’t find it. I planned to rename or delete the file so I could get rid of the error message.
Any advice where to look for the file?
Please help.
Thanks.
