I recently came across an error in Outlook 2010 where I couldn’t open any attachments and received the following error:I did some testing and found that it did not matter which file was chosen, none of them would open. So, I knew they couldn’t be corrupt. I tried to run an Office Repair to see if Office was corrupt, but that did not resolve the issue. I tested it in Safe Mode and found that didn’t help either. After saving to the desktop, I was able to right click, go to properties, select unblock and I could open the document.
However, this clearly wasn’t the end solution.
After some research, I found that it was not Office itself, but it was a DCOM misconfiguration. I went through the following steps to resolve this issue:
- Open run and type dcomcnfg
- Expand Component Services
- Expand Computer
- Right click My Computer and select Properties
- Select the default properties tab and set the following:
Default Authentication Level: Connect
Default impersonation Level: Identify
The problem is solved.
