Outlook: Cannot create file: {filename}. 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.

Introduction

When opening an attachment directly from within Outlook you could get an error message saying that it can’t create the file and to that you need check the permissions on the folder you want to save it in.
In most cases the permissions on the folder isn’t the issue but the fact that the folder is “full”. When you open an attachment directly from within Outlook it will first save a copy to a subfolder of the Temporary Internet Files folder.
Update on 01/21/2015: Re-read the article. In my rush of initial write, I had duplicate information. Cleaned this up to streamline the fix details. Clarified a couple semi-ambiguous statements. Added a comment below to answer questions.
Update on 02/10/2016: Minor changes to article.

Steps (6 total)

1

Preface: Identify the Outlook Secure Temp folder

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We need to start by finding the Outlook Secure Temp folder. Unfortunately this is easier said than done.
The subfolder name Outlook creates (on installation of Outlook) in the Temporary Internet Files folder is somewhat random.
In Outlook 2003 and previous, the folder name starts with "OLK" and is followed by up to 4 random numbers or letters. In Outlook 2007, 2010 and 2013, this folder is called "Content.Outlook" and then has a subfolder which is named with with 8 random numbers and letters.
In addition, by default, you cannot simply browse to the folder to clean it out. Getting to the Temporary Outlook Folder can still be accomplished in 2 easy steps though.

2

Step 1: Locate the folder

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The folder location is stored in the registry in the following key, which varies with version.
Outlook 97 is --------- HKEY_CURRENT_USER\Software\Microsoft\Office\8.0\Outlook\Security
Outlook 98 is --------- HKEY_CURRENT_USER\Software\Microsoft\Office\8.5\Outlook\Security
Outlook 2000 is ------ HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\Security
Outlook 2002/XP is - HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Security
Outlook 2003 is ------ HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security
Outlook 2007 is ------ HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Security
Outlook 2010 is ------ HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Security
Outlook 2013 is ------ HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Security

3

Step 2: Get to the folder

Open the OutlookSecureTempFolder registry key from the location provided in Step 1.
Copy the path from the key.
Open Explorer
Paste the address in the Address Bar and press Enter

4

Delete everything

Ctrl + A, Delete.
Toss it all. This should fix the issue.

5

3rd party tools, automation options

OutlookTempCleaner focuses only on dealing with the SecureTempFolder and can also be used in (corporate) login and logoff scripts to clean up the folder without any end-user interaction. See references.

6

Option: Change the folder (taken from comments)

Another noteworthy workaround I've provided for some of our most-commonly-affected users is to outright change the secure temp folder.
*** Please note, I am not suggesting this as a best practice, but rather as a practical solution. ***
Case:
Win 7, latest SP & Updates.
Office 2013, latest SP & updates.
Start:
0: logged the affected user off of the PC. Rebooted for good measure.
1: Logged in with affected user account, then ran regedit with my own elevated privileges.
2: Browsed to the HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Security (as similarly seen in second screenshot in step 2.)
3: Renamed registry key OutlookSecureTempFolder to OutlookSecureTempFolder__Old
4: Created a new REG_SZ, named OutlookSecureTempFolder
5: Created the registry value as %USERPROFILE%\Documents\OutlookTempFiles\
Note: special attention to the trailing whack. You need this.
6: Created the new folder in the above location (just make a outlooktempfiles folder in users' Documents folder. Typical NTFS permission inheritance should be fine - nothing special.)
7: Restarted, logged back in, ran Outlook.
Presto. now Outlook is storing the temp files in that new location for that user.
Step 8: Teach/educate the user!
example:
Ok (user), when this happens again, and it will, go here, and move these items to your recycle bin. I'll help you out by making a Note in your Outlook notes folder that will remind you of exactly how to do it. So when it happens, just re-read these instructions, Lastly, don't forget to close-reopen outlook afterwards,and it should be right-as-rain once again.
- in this alternative solution scenario I was able to overcome the hurdle by providing a solution that was simple enough for my user to do. It's worth mentioning that I feel this particular user is above-average when it comes to working with their PC. Other, less skilled users may simply need to send in a helpdesk request each time it happens. Your mileage may vary.

Source: https://community.spiceworks.com/how_to/84474-outlook-cannot-create-file-filename-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