This is the error I get trying to connect to my Time Machine (The server may not exist or it is unavailable at this time. Check the server name or IP address, check your network connection, and then try again.) This is the error I get. I've tried renaming the Time Machine and renaming the apple.com.loginitems.plist file and neither worked. It worked for awhile then stopped when I trying to transfer a file from the Time Machine to my MacBook.