Event ID 4227 Source TCP

[Daunted Yeti]

I have a client that has been having consistent issues with error 4227 being thrown by any and all of their workstations and their server.  I've spent several hours attempting to diagnose this issue, and I've gone through a ton of threads on technet and such. I'm getting 2 or 3 per day and I read in a post that increasing MaxUserPort and TcpTimedWaitDelay that it should stem the tide of the issues. 

On a possibly related issue, (I'll get back to the main issue in a moment) the client uses google app sync for their email services and has had pretty consistent sync issues with them having to manually sync a second time after the first one almost always fails.

Back to the main topic, once I added those settings to one machine in their environment, the error stopped coming from that machine and the user no longer had any sync issues for 5 days. Today the error is back with a vengance, although I saw the error twice this morning with no associated sync issues, then a sync issue with no associated error. I find it hard to believe that 5 days ago I made the change and both stopped, and now their both acting up again at the same time. it doens't make sense that they aren't related somehow.

I've deployed the registry change onto the rest of the computer (I did that before the error started again) and it's been quiet, but I'm fairly certain its not resolved.

 

A little addt'l information, they're running SBS 2011 essentials, a few specialized applications for their industry, although all the machines are having issues, and that software isn't installed on all the machines, so I don't think its related.

 

If anyone has questions about netstat, I haven't been in a position to run it as soon as the error presents itself and I haven't had the time to write a powershell script to capture netstat -ano once on event trigger or some such.

 

Please let me know if you can help.