How to fix a stuck Time Machine backup

I hit a wall yesterday with my MacBook Pro.

(My tweeting went downhill from there.)

In short, Time Machine would start, but get stuck after just a few moments. Sometimes, it would stall on Preparing Backup… and other times, it’d get a couple of hundred megabytes done (out of several gigabytes it needed to do) then stop.

I turned tried turning Time Machine off and rebooting, but had no luck. No matter what I did, the backup wouldn’t complete.

I did some Googling, and came across a trick I had forgotten about: nuking the .inProgress file from orbit.

This file lives on the Time Machine drive, and is used a temporary cache as files are copied. Sometimes, it get corrupted, halting any further backups. Here’s how to get rid of it and keep the backups flowing.