Q: I can no longer sync my Mac with iPhone for Messages.

This could be a complicated problem to solve, as there are many possible causes for it. Please test after taking each of the following steps that you haven't already tried. Back up all data before making any changes.

Before proceeding, test on another network, if possible. That could be a public Wi-Fi hotspot, if your computer is portable, or a cellular network if you have a mobile device that can share its Internet connection. If you find that iMessage works on the other network, the problem is in your network or at your ISP, not in your computer.

Step 1

Check the status of the service. If the service is down, wait for it to come back up. There may be a localized outage, even if the status indicator is green.

Step 2

From the menu bar, select

           ▹ System Preferences... ▹ Date & Time ▹ Time Zone

The nearest city to where you are should be selected on the map.

Step 3

Sign out of iMessage and FaceTime on all your Apple devices. Log out and log back in. Try again to sign in.

Step 4

Restart your router and your broadband device, if they're separate. You may have to skip this step if you don't control those devices.

Step 5

Follow these instructions to display the machine's serial number. If the number is missing or invalid according to this web form, take the machine to an Apple Store or other authorized service center to have the problem corrected.

Step 6

Take the steps suggested in this support article. If you don't understand some of the steps or can't carry them out, ask for guidance. Note especially that the email address associated with your Apple ID must be verified. If the address is in the obsolete domain mac.com, you'll have to change it.

Step 7

From the menu bar, select

           ▹ System Preferences... ▹ Network

If the preference pane is locked, click the lock icon in the lower left corner and enter your password to unlock it. Then click the Advanced button and select the Proxies tab. If the box marked SOCKS Proxy is checked, uncheck it. You don’t need to change any other settings in the window. Click OK and then Apply. Test.

The result may be that you can't connect to the Internet at all. Revert the change if that happens, or if iMessage still doesn't work. Remember that you must Apply any changes you make in the preference pane before they take effect.

Step 8

Select from the menu bar

           ▹ System Preferences… ▹ Flash Player ▹ Storage

and click

          Block all sites from storing information on this computer

Close the preference pane.

Step 9

Make sure you know the ID and password you use with iMessage. Launch the Keychain Access application in any one 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 and start typing the name.

Use the search box in the toolbar of the Keychain Access window to find and delete all items with "iMessage" or "com.apple.idms" in the name. Log out and log back in.

Step 10

Enable guest logins* and log in as Guest. Don't use the Safari-only “Guest User” login created by “Find My Mac.”

While logged in as Guest, you won’t have access to any of your personal files or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.

Test while logged in as Guest. After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.

*Note: If you’ve activated “Find My Mac” or FileVault, then you can’t enable the Guest account. The “Guest User” login created by “Find My Mac” is not the same. Create a new account in which to test, and delete it, including its home folder, after testing.

If iMessage worked in the guest account, stop here and post your results.

Step 11

Start up in safe mode and log in to the account with the problem.

Note: If FileVault is enabled in OS X 10.9 or earlier, or if a firmware password is set, or if the startup volume is a Fusion Drive or a software RAID, you can’t do this. Ask for further instructions.

Safe mode is much slower to start and run than normal, with limited graphics performance, and some things won’t work at all, including sound outputand Wi-Fi on certain models. The next normal startup may also be somewhat slow.

The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

Test while in safe mode. After testing, restart as usual (i.e., not in safe mode) and test again.

If iMessage worked in safe mode, but still doesn't work when you restart in "normal" mode, stop here and post your results.

Step 12

Triple-click anywhere in the line below on this page to select it:

/Library/Preferences/com.apple.apsd.plist

Right-click or control-click the highlighted line and select

          Services ▹ Reveal in Finder (or just Reveal)

from the contextual menu.* A folder should open with an item selected. Move the selected item to the Trash. You may be prompted for your administrator login password. Restart the computer and empty the Trash.

*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combination  command-C. In the Finder, select

          Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You may not see what you pasted because a line break is included. Press return.

Step 13

Reset the NVRAM.

Step 14

Reset the System Management Controller (SMC).

Step 15

Reinstall OS X.

Step 16

If none of the above steps resolves the issue, make a "Genius" appointment at an Apple Store, or contact Apple Support. When you set up a support call, select "Apple ID" as the product you need help with, not the hardware model. That way, if you're not under AppleCare, you may be able to talk your way out of being charged for the call.

Thank you for all of the above steps.

What happened when you took Step 16?

Hi,

Linc's list has been brought about by several years of several similar looking symptoms that appear to show the Apple ID on the Mac version of Messages is not logged in or at least not fully.

Step 5 is important for Messages as it needs the Serial Number to make a device Specific Login to the iMessages Server.

This means that checking it can help pin point the issue.

That will will need solving before moving On.

Step 10 (Try a  completely new Mac User Account created for this test or the Guest account) is the next step to see if it is the Whole Mac (every User) or just one account.

I suggest Step 11, 13 and 14 after this as these can reset items that are not dealt with by other restarted and maintenance.

I have never seen a Reinstall, Update or Upgrade work when it is this reduced list.

It seems the Feature to prevent others trying to log in as you gets triggered and you cannot reset this from your computer.

The Only Fix at this point is to contact Apple Support (Same as Apple Care) and tell them you have an Apple ID issue connected to your Mac's Use of your Apple ID on the iMessages server.

Apple ID issues are free to fix but the issue is then dealing with the Level 1 Responders who tend to be Script led.

You need to ask to speak to someone higher.

From those that post back on this issue it seems that not all Level  2's are aware and will still want you to try things and then Reinstall first. (or Update if you are not on the "Latest" or Upgrade if not using El Capitan at the time of writing this).

Apple are aware that there is an issue and they do ask the Level 2s to gather data.

If you insist that they Reset the  server (for your Mac's use of the Apple ID) then they will (according to posts back) involve the engineers.

It seems they are the only ones allowed to reset the server details now.

The people who have posted back have been told between 24 hours (overnight) and 5 days  with a promise of a call back to see if the issue is resolved.

Most report they never got a call back but the issue was fix was fixed (or went away) within the time frame they were told.

Summary,

Apple Care/Support can sort this but it takes moving up the chain until you reach someone that can access others that can reset the server.

It will involve either testing (Linc's list is a good place to cover everything) and data gathering to help them solve the issue as a whole.

It's up to you how much time you want to invest in that verses being polite enough to get the issue fixed.

7:57 pm      Saturday; July 30, 2016

    for the      Points.

7:19 pm      Sunday; September 11, 2016