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Thank you for the links below. Unfortunately I have already tried all these methods and have been unsuccessful. I am also able to send but not receive @me.com messages on the Mail app on my Mac. Do I need to take the Mac to my nearest Apple store for them to enter the details manually as I cannot get a manual option on Mail. ? Hoping you can help.
Thank you for using the Apple Support Community. Due to the nature of your issue or question you may find more information by using another one of Apple's support resources - https://expresslane.apple.com/GetproductgroupList.action.