Hello @Danny Dao
I think this was an know issue related with the TMG version:
You can also check the resolution provided in this article. It might be related too:
Event ID 105 — NLB Denial-of-service Protection
https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/cc726481(v=ws.10)?redirectedfrom=MSDN
Hope this helps with your query!
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