Outlook could not create the work file error

Every Outlook start greets me with Outlook could not create the work file. Check the temp environment variable. Outlook then mostly works but images in mail often refuse to load.

My TEMP variable looks normal in System Properties. What work file does it mean?

The error's advice is a red herring, which is why your TEMP check found nothing. The work file lives in the Explorer cache location, not TEMP. The message means the registry value naming that location points somewhere invalid, usually after a profile migration, a disk cleanup tool or a folder redirection change.

1

Open regedit and navigate to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders.

2

Find the value named Cache. On a healthy system it reads %USERPROFILE%\AppData\Local\Microsoft\Windows\INetCache. Yours will show a dead path, an old username, a disconnected drive letter or a folder that no longer exists.

3

Double click Cache and set it to exactly %USERPROFILE%\AppData\Local\Microsoft\Windows\INetCache, keeping it as the expandable string it already is.

4

Sign out of Windows and back in so Explorer rereads the value, then start Outlook. The error is gone and the broken image loading, which depended on the same cache, heals with it.

The images detail confirms the diagnosis nicely: Outlook renders remote images through the same cache machinery, so a dead Cache path breaks both the work file and image display together, and both recover together. If you find the value already correct, the rarer variant is permissions, the INetCache folder existing but unwritable, fixed by checking its security tab grants your user full control.

Cache pointed at a username from two laptops ago. Corrected it, signed out and in, no error and images load everywhere. The TEMP advice cost me two evenings before this thread.