It uses a Mac feature called sparse bundle disk image so that any filesystem can be made to look like it’s a native HFS+ file system. You see, Time Machine works by simulating a virtual disk over the network. The problem is so deeply rooted inside Time Machine’s architecture that there isn’t much that Apple can do except to re-engineer their entire approach of network backups. There have been many complaints about this in the interwebs and even in Apple’s own support forums and there isn’t any viable solution so far – except for not using Time Machine over Wi-Fi to backup laptops and stick to local USB drives instead. If the network ever gets interrupted while Time Machine is doing its thing, there’s a good chance of you corrupting the entire backup volume. You’re likely won’t be happy with your decision, especially if your home network is primarily on Wi-Fi. On the other hand if you’re thinking to buy a Time Capsule or some other 3rd party NAS (Network Attached Storage) devices like Synology DiskStation or WD MyBook Live and use them primarily for using it with Time Machine, think again. However hard this may seem, it looks like there isn’t a way around it – you’ll need to switch to local drives for your Time Machine backups from now on. If you’d ever saw that message, you’ll know how disappointing it felt when you had to lose months’ worth of Time Machine backup. The error message above can be a common sight for people who uses Time Machine over Wi-Fi to safeguard their Mac’s data.

To improve reliability, Time Machine must create a new backup for you. Time Machine completed a verification of your backups on “”.

Time machine won&#39;t backup

Time machine won't backup