Messages.app/Facetime Broken/Not-Working in Yosemite 10.10

Question

Hi all.
I'm wondering if anyone else is having a problem with Messages.app/iMessage/Facetime after upgrading/installing Yosemite (the release version)? My Messages doesn't work.
The Problems
(A) Specifically, when you enter your AppleID in Messages.app->Preferences->Accounts->iMessagesAccount you get the following error:
Quote: 
Could not sign in to iMessage.
Could not sign in. Please check your network connection and try again.
Sometimes the error says it cannot activate. 
(B) Also, oddly, FaceTime makes me enter my AppleID every time i reboot, but will work for Video FaceTime chats, but not audio?  And once I reboot, it again asks me for my AppleID.
My Setup
 I have a 2010 Mac Pro. My Mac Pro is not stock, but nothing that's in there *should* cause a problem, so I wonder if anyone else is having a similar issue. My non stock hardware is:
--MacVidCard 802.11ac and bluetooth 4.0 upgrade card (http://www.macvidcards.com/store/p33...port_Card.html)
--VisionTek 7750 Eyefinity 6 2GB card (https://www.visiontek.com/graphics-c...rd-detail.html)
--OWC Mercury Accelsior E2 SSD (http://eshop.macsales.com/shop/SSD/P...Accelsior/RAID)
--Inateck 4 port PCI-E to USB 3.0 card (which has requires no drivers and is a pretty compatible card) (http://www.inateck.com/inateck-kt400...er-connection/)
--Upgraded the 12-core 2.66ghz motherboard to 12-core 3.46 west mere x5690 xenon (turnkey OWC upgrade) (http://eshop.macsales.com/shop/turnk...Xeon_Processor)
Here is some of the troubleshooting I've already done:
I tried making a new guest account and tried to login there, and went so far as to install a clean install on a blank external drive with similar results.The only caveat is when you make the new guest account of fresh install, when you first put in your AppleID it almost kinda succeeds.  You initially see the screen where Messages tells you it's associating your phone number and a few email addresses together.  But if you try to use Messages, nothing gets through, and when you quit and re-run the app, you get that same 'could not sign in' error.
Went through the stuff here to no avail:messages "An error occurred while activating. Try again later"
My serial number does show in about this Mac.
Messages/iMessage/Facetime all work(ed) fine under 10.9.x on the Mac Pro, so it should not be a hardware issue, as I didn't change any hardware over after upgrading.
I installed Yosemite on my 2013 13" Macbook Pro and Messages/Facetime all work fine, so it's likely nothing to do with my network.
I have confirmed that others that have done the MacVidCard 802.11ac/bluetooth upgrade are not experiencing this issue.
Same with the USB card.
Since I installed a fresh OS on an external drive, I doubt the OWC Accelsior has anything to do with this.
I called apple support, and they are stumped and getting engineers to figure it out. One support guy at apple said the broken Messages.app problems were his only unresolvable problem he was getting this since Yosemite launched (and that it has been an exceptionally smooth launch), and had 4 calls on the same issue early morning the day after launch (he's one level up from the entry support folks and the only level above him are the actual software engineers).
The video card seems highly unlikely to matter here. Then again, I'm not sure the hardware should matter at all...Which leaves me with...
My Suspicion
I think there may be an interplay between 2 things going on.  One, although I haven't changed my motherboard, perhaps changing the processor tray makes something fail with the Messages authentication?  And second, perhaps there is some corrupted data up on iCloud that alone or in combination with the processor tray, is tripping up Messages verification? The solution might be to bring my machine in and have them do some magic to make the serial number authorized on their system?
Appreciate any thoughts and thanks for any help. Thanks!

Answer 1

Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Console in the icon grid.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen. Click the Clear Display icon in the toolbar. Then take one of the actions that you're having trouble with. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.
Please don't indiscriminately dump thousands of lines from the log into this discussion.
Please don't post screenshots of log messages—post the text.
Some private information, such as your name, may appear in the log. Anonymize before posting.