I can't log in to Messages or FaceTime with my iCloud account.

This is absolutely ridiculous. I have not been able to sign in to Messages since my last upgrade. Is there going to be a fix for this or what? All my friends are making fun of my computer's handicap. A state of the art computer that won't let you sign in to messages? Really? I tried everything to fix this and I am sic of wasting time on something that should take literally half a second to do. (sign in)

I finally did a clean install about a month ago, not a restore from time machine. Yes it's tedious but it worked.

Go into install mode, disk untilities, wipe the hard drive and reintall. Set up as new mac, then install all your apps. Extreme but it worked.

No,

I'm not about to do open surgery on my computer for a chat program that should "just work". I'll just let it be and wait for a solution. The sooner the better, because I am very vocal about this issue and I think I've turned everyone around me off the brand because they are tired of hearing me complain that I am unable to sign in to one of the main features of my computer, messages.

Hi,

Is there any chance to upgraded from prior to OS X 10.8.2 when the Messages version in Mountain Lion became version 7.0.1 ?

At this particular update the app needs the Serial Number to be present on the Logic/Mother board.

The number can be missing if the board has been replaced during an repair or refurbishment.

To check use the Apple icon menu > About this Mac.

Click twice on the line that tells you the current OS.

It will change to the Build number and then the Serial Number.

If it is missing you will have to visit an Apple Store or Apple Authorised Service Provider to have it replaced.

The people that are reporting back about this are not getting charged.

8:37 pm Tuesday; December 24, 2013

 iMac 2.5Ghz 5i 2011 (Mavericks 10.9)
 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb (Snow Leopard 10.6.8)
 Mac OS X (10.6.8),
 Couple of iPhones and an iPad

As a matter of fact, my Mac mini's logic board was replaced in 2011. The serial number is missing from About This Mac as well.

I used the Send message capability in the Notification center (far right at the top), and once I had sent and received a reply message, Messages was working.

I'd just like to affirm that Ralph Johns is correct - my messages wasn't working either on my Mac Pro - and it had a logic board replaced. I googled and found the utility to set the serial number, and once I did so messages starting working. What a bizarre problem - but ensuring the serial number is set for your comptuer is indeed the solution!

same here, pulled ethernet cable to go wireless, connected again and messages won't login forever. goodbye messages. can't login facetime neither but even when I could it went "facetime can't connect" so these programs are totally useless.

hi,

If what you are saying is that you have WiFi and Ethernet connected to the router at the same time (Your computer has two IP addresses) then disconnect one of them.

I would also try resetting the Keychain.

7:30 pm Thursday; January 23, 2014

 iMac 2.5Ghz 5i 2011 (Mavericks 10.9)
 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb (Snow Leopard 10.6.8)
 Mac OS X (10.6.8),
 Couple of iPhones and an iPad

thank's john

my facetime and i massage its working,, now

This issue is pure agony and has been dragging on month after month now... I upgraded to Mavericks (multiboot) and after all this messing around I finally logged in (or so I thought!) Set up a few jabber accounts, a bonjour accouhnt and then had a peek at my account list only to find iMessage inactive - so tried to log in again only to find that The account could not be used with iMessage at this time??? WHAT?

Meanwhile on Mountain Lion exerything is fine...on iPhone...fine... My problem seems to be Mavericks!

I cleaned the caches, preferences, deleted the Messages folder in user Library tried to stop the imagent service,,, nuked my keychain, rebooted and STILL the same behaviour.

I believe that developers working on 10.9.2 are being asked to concentrate on messages, mail etc but are they addressing this issue that affects just about everyone whether theey are on OS X or iOS7,,,, i's a real mess.-

While setting up one of my bonjour/gmail accouts I checked the sync buttons for everything including calendar.. and the notification center started going nuts!!! I mean big time. I dismisse dor deleted a notification and it kept coming back... so I unsynced mail and calendar in the Internet accounts and still the calendar kept relaunching and the notification center going nuts! I disabled notifications did a Repair Permissions and rebooted and seemingly for now at least the cancer is gone...

Would 10.8.6 ot have been a better idea... Mavericks is still a liong way from stable - try splitting finder tabs by "dragging one off" and it leaves a nasty miniature window artefact right there on the desktop that only a finder relaunch can cure...

Back to Mountain Lion so for the forseeable future... More than 6 months later and still tis messages issue drags on!

I haven't even upgraded from 10.5.8 as I was too scared to following the utter lack of anything positive anybody had to say about it. I also, despite Mavericks being nothing to do with my particular set up, am suffering from all of the issues described above and cannot for the life of me sign into iMessage on my computer (the most expensive home computer money can buy) despite it working fine on my iPhone and iPad. Support have not been able to help me and the guys in the Mac store evidently think I am an idiot. This issue has prevented me from choosing to upgrade to the new Mac Pro as it is has affected my work so badly, and the apparatus in place to remedy such minor issues is so fundamentally & woefully inept that I shudder at what horrors await me should I make that choice...

You didn't ask my opinion, but I personally think that's a bad move and gross overreaction. Just buy the mac pro, get os x 10.9, and enjoy. There are some small downsides, but overall 10.9 is way better than 10.5.8. Just my opinion! :-)

Hi,

OS X 10.5.8 is the last version of Leopard.

Did you mean OS X 10.8.5 (the last version of Mountain Lion) ?

If it is Mountain Lion then can you check the Version number of Messages ?

Go to the Application Folder, highlight the App and use CMD + i keys together (Get Info).

In the top section of the Info Panel will be the Version Number.

It should be version 7.0.1

This was actually updated at OS X 10.8.2

Since this time you have to have the Serial Number of the Mac actually on the logic/mother board.

Use the Apple Menu > About this Mac

Now click twice on the line that reads the OS version.

This will change to the Build Number (Another OS counting method) abd than to the Serial Number.

This should match the number on the bottom/back/battery compartment of your computer.

You may need to take it to a Store if it is missing.

10:07 pm Friday; February 21, 2014

 iMac 2.5Ghz 5i 2011 (Mavericks 10.9)
 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb (Snow Leopard 10.6.8)
 Mac OS X (10.6.8),
 Couple of iPhones and an iPad

I had the same iMessage login issue and although 'Set date & time automatically' was checked, the value that was set for the Apple time service URI wasn't present in the list to the right of the checkbox.

I chose 'Apple Europe' from the list and was then able to log in to iMessage.