Using classic Outlook for Windows in business environments
Hello Ian Turner
When you open an attachment directly from Outlook, Outlook first saves the file to a temporary folder such as:
C:\Users\xxx\AppData\Local\Microsoft\Windows*INetCache\Content.Outlook*
The error:
"You do not have appropriate permission to perform this operation"or"Failed to open document..."
suggests that Outlook is unable to access or launch the file from this temporary location.
Base on these information, I suggest that you can try below steps to double-check the issue at your end:
1/ Save the attachment to your Desktop and open it
- Save the attachment to your Desktop and open it
- In Outlook, right-click the PDF attachment and select Save As.
- Save the file to your Desktop.
- Open the saved PDF.
--> If the PDF opens normally, the file itself is likely not the issue, and the problem may be related to how Outlook is opening attachments.
--> If the PDF cannot be opened even from the Desktop, the issue may be related to the PDF viewer or the file itself.
2/ Clear Outlook's temporary attachment cache
Outlook stores attachments in a temporary folder before opening them. If this cache becomes corrupted or overloaded, attachments may fail to open.
- Close Outlook completely.
- Press Windows + R.
- Enter:
%localappdata%\Microsoft\Windows\INetCache\Content.Outlook - Open the folder that appears.
- Open the subfolder(s) inside Content.Outlook and delete the files stored there. These are temporary copies of Outlook email attachments and will be recreated automatically when Outlook downloads attachments again. Do not delete the Content.Outlook folder itself.
- Reopen Outlook and test the attachment again.
3/ Check whether security software is blocking Outlook.
Antivirus or endpoint protection software can sometimes prevent Outlook from opening files stored in its temporary cache location. If applicable, review any recent security software changes or logs.
4/ Verify the default PDF application.
- Right-click any PDF file on your Desktop.
- Select "Open with" > "Choose another app".
- Verify whether "Microsoft Edge" is set as the default PDF viewer.
- Open the PDF directly from the Desktop using Microsoft Edge.
If another dedicated PDF viewer is installed on the device, you may also consider updating or repairing that application to rule out any issues with the PDF handler.
Please let me know if I can do anything more for you.
Kind regards,