The students are doing some work on encryption and copyright and we have been having a problem with setting passwords on powerpoint documents.

We have a full install of Microsoft Office 2003 on all PC's. In Excel and Word you can go to 'Tools > Options > Security' and assign a password and it works. When users try that in Powerpoint it doesn't work and when you click 'advanced' there are no encryption types (there are in Word and Excel).

Logging on as administrator you can password protect a Powerpoint and see all the encryption types. Obviously we don't want to give all the students admin rights, anyway it works in Word and Excel without any rights.

Trying to add encryption by going to 'File > Save As > Tools' produces the same result (works in Excel, not in Powerpoint)

any ideas? Thanks in advance