iMessage and FaceTime
Well, it used to work fine. But suddenly both iMessage and FaceTime are problems. I can text on my iPhone but cannot log into iMessage or FaceTime on my desktop. All software is up to date and yet each time I try to log into iMessage, I get a message stating there is an error during activation. Same on FaceTime. I've been trying to fix this all night.
iMac, OS X Yosemite (10.10.3)