Hi @Gareth Davies
Thanks for your feedback above which shared more information and glad to know that your issue is resolved now! Since our forum has the policy that The question author cannot accept their own answer. They can only accept answers by others, and according to the scenario introduced here: Answering your own questions on Microsoft Q&AI would make a brief summary of this post so that other forum members could easily find useful information here:
[Skype for business patches listed but Skype not installed - Summary]
Issue Symptom:
Skype for Business was removed some time ago but Windows update keeps saying I need to install patches for Skype for business.
Solution:
Carefully pick through the registry, delete keys that are specifically and exclusively Skype for Business Server.
Reference Links:
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