The Outlook File Attach menu has a list of recently opened files, and there is an issue where it does not stay current with the latest recent items.
I'd suggest try clearing the recent items.
I've made a script to backup and clear the list of recent items. Instructions below.
This clears pinned folders, so afterwards, re-pin your favourite folders in Explorer's Quick access.
e.g. here's my Quick access showing pinned and recent items -
Your recent items are stored in the folder locations below. These are the locations that get cleared when you reset.
- %APPDATA%\Microsoft\Windows\Recent Items
Script to backup and clear Recent items
- Copy below code and paste it into Notepad, and save it with the file extension ".bat"
- Run the .bat file
- Restart Outlook and test
- Re-pin your favourite folders in Explorer
robocopy %APPDATA%\Microsoft\Windows\Recent\ %TEMP%\Recent\
del /F /Q %APPDATA%\Microsoft\Windows\Recent\*
del /F /Q %APPDATA%\Microsoft\Windows\Recent\AutomaticDestinations\*
del /F /Q %APPDATA%\Microsoft\Windows\Recent\CustomDestinations\*
taskkill /f /im explorer.exe