Problem opening attachements in Outlook without first saving them.

You get following Error:
"Cant create file: document.pdf. 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."

Why does this happen?
In my findings the cause of this error was due to many documents that had same name stuck in microsoft office temp folder. Let's say you are emailed daily report that is always called report.pdf. After some number of times this document is opened from outlook (I think number is 99 times), you will start receiving above error.

How do I resolve it?
1. Open REGEDIT.EXE and go to Edit -> Find... In the Find dialog box type "OutlookSecureTempFolder" without the quotes and locate that registry key.

2. That key will contain the actual folder location, and will look like:

C:\Documents and Settings\%USER_NAME%\Local Settings\Temporary Internet Files\OLK#\ (where # is a random letter or number)

3. Copy the location of that folder.

4. Click on Start -> Run... and paste the folder location from step #4 then click OK.

5. Windows Explorer will open that folder. Please, delete all files present.

6. Restart Microsoft Outlook and you should be able to open your attachments.