Unable to open PDF files in Outlook Error: Can't create file: . Right-click the folder you want to create the file in and then click Properties on the shortcut menu to check your permissions for the folder.

This is quick solution.

1)Close outlook, and search registry editor by search button in Windows 10

2)Go to path given in picture

3) Right click on key OutlookSecureTempFolder and select modify

4) Browse to path in windows explorer and delete everything from that folder

5)Re-open outlook and check 

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