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Cannot retrieve information from Viso Services: Error 20021

Last updated: Aug 24, 2026

The is error is caused by Windows firewall blocking the Viso Services. To disable Firewall on all Viso computers:

  1. Open Control Panel > System and Security
  2. Click Windows Defender Firewall
  3. Click Turn Windows Defender Firewall on or off on the left side of the window.
  4. Under Overview, click Windows Firewall Properties
  5. In each network zone, select Turn off Windows Defender Firewall (not recommended)
  6. Click Close

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