It's not a connection issue. It's a SE issue and has been a SE issue since patch 1.16. Before this patch was my 30 free play and I NEVER had an issue with 90k or 2002 and I can honestly say I never heard of those codes till 1.16. Since the patch I have upgraded my internet connection twice, moved my router closer to my pc, and upgraded to a better router.
There is no way it's on the users end at all.