Citrix Support states in CTX101639:

CTX101639 - Event 1020 Gemini Installer error in Event Viewer

This document was published at: http://support.citrix.com/kb/entry.jspa?externalID=CTX101639

Document ID: CTX101639, Created on: Mar 24, 2003, Updated: Apr 23, 2003

Products: Installation Manager for MetaFrame XPe

Symptom

Event ID 1020 is Source Gemini Installer in the Event Viewer.

Cause

There is an invalid value for the following registry key:

HKEY_LOCAL_MACHINESOFTWARECitrixIMS2.0ADF

Resolution

Delete the value below:

"NetAccount"="DomainNameUserName"

Additional Information

This can be reproduced by adding a bogus value and string and then restarting the ADF installer service.