Steps how to reproduce with Server Installation of "LibreOffice 3.6.0beta1 English UI/Locale [Build-ID: 1f1cdd8] on German WIN7 Home Premium (64bit)
1. download sample document
from "Bug 51072 - FILESAVE as .ppt makes Vertical letters in
"VerticalText" fontwork horizontal"
2. Save as .ppt under new name from LibO File Menu
Actual: "Error saving the document. Write Error. The file could not be written"
Save as .odp works fine
I did not check with what version the problem started
"Bug 51179 - FILESAVE cannot save file as .ppt" is a DUP, but I mark this one as DUP because Bug 51179 has more research results
*** This bug has been marked as a duplicate of bug 51179 ***