What Causes the “Can’t Sign into iMessage” Error on Mac?

We found the underlying causes to be:

Solution 1: Checking Date and Time

If the Date and Time settings have been glitched and the computer is using a false Date and Time, the error might be triggered. Therefore, in this step, we will be reinitiating the automatic check for date and time which will force the computer to correct this mistake. For that:

Solution 2: Signing in to iMessages

In some cases, the Apple ID might get glitched due to which the error might be triggered, Therefore, in this step, we will be re-initiating the sign in to iMessage. For that:

Solution 3: Clearing NVRAM

It is also possible that the NVRAM might be storing data that is preventing the computer from being able to log-in to your account. Therefore, in this step, we will be clearing all the data being stored in NVRAM and it will be regenerated automatically by the computer. In order to clear the data:

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