If you are unable to open PDF/Word Documents after saving them from Outlook or Edge, it is likely that the file is blocked, which is preventing the document from opening.
In order to fix this, try the following:
Right click on the document in question
Click Properties
Select the General Tab (should automatically default here anyway)
Towards the bottom, if there is an option for Unblock, please TICK this option
Click Apply, then OK.
After doing this, the document should open as normal.