If Outlook closes unexpectedly, like during a system update or reboot, the windows you had open in your last session may not reopen by default. To restore your previously open windows, open a command prompt window and run the command below (note the space between .EXE and /):
C:\Program Files (x86)\Microsoft Office\root\Office15Office16\OUTLOOK.EXE /restore restore
You can create a desktop shortcut for this command to quickly restore your windows anytime:
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