Adobe Acrobat can occasionally stop responding while leaving several background processes running.
Closing the main Acrobat window may not terminate all of these processes, which can prevent Acrobat from opening correctly again.
You can force close the remaining Adobe Acrobat processes using PowerShell.
Open PowerShell and run:
Get-Process | Where-Object { $_.ProcessName -match 'Adobe|Acrobat|Acro' } | Stop-Process -Force
This will forcibly terminate running processes with Adobe, Acrobat or Acro in their process name.
Once the command has completed, try opening Adobe Acrobat again.
Important
This command forcibly closes matching Adobe processes.
Make sure any Adobe applications are no longer being used before running it, as unsaved work may be lost.
If Acrobat regularly stops responding, force closing the processes is only a temporary fix. The underlying problem may require Acrobat to be updated, repaired or reinstalled.