Why can't Time Machine see shared drive? I am having trouble setting up a Time Machine backup to a shared network drive. I have an external drive plugged into a MacBook Pro (MBP), and I want to use Time Machine to remotely back up a MacBook Air (MBA) to it. I followed the instructions in “Can Time Machine back up to an external HD connected to another Mac?” but Time Machine will not present the remote drive as an option.


The drive is formatted properly. I have an identical partition to which the MBP does a local Time Machine backup.
The drive is shared properly. In fact, the MBA can see and mount the remote drive.

However, the partition is not shown as a potential Time Machine drive.



Finder can see and access the drive, so why can't Time Machine? Is there a bit somewhere I can flip to tell Time Machine to see it?
When you click the "Options..." button in the File Sharing preferences, is "Share files and folders using AFP" enabled? Time Machine over the network requires AFP, so it won't work if only SMB is enabled.

You may also need to disable SMB. I am not exactly sure why this is the case, but sometimes the SMB share takes priority and Time Machine can't seem to see the AFP share. Note that this will prevent Windows clients from connecting to file shares.