So I came across this error in my Mac OS X system.log while performing a Time Machine backup:

backupd[]: Unable to rebuild path cache for source item. Partial source path:

I don’t know about you, but when I see errors from my backup daemon, I pay attention.

I first forced a reindex of Spotlight on the source device by removing the metadata:

sudo hdutil -E /

Spotlight got busy again, but after 20 minutes, I saw log entries along the lines of:

mdworker[]: ATSFontFindFromContainer failed: count = 2

And when I say lines, I mean hundreds of them.  Disk Utility returned OK on both devices, but Spotlight seemed to be spinning its wheels:

mdworker[]: (Error) Import: Importer force killed!

I “validated” the integrity of the fonts in Font Book, only to find csd12.ttf gave a warning.  After removing the font, Spotlight finished indexing in 30 minutes. With no more log errors, Time Machine now seems content to copy my files hour after hour.

So could it be that a bad font caused problems for OS X’s backup mechanism?

I’ve read several blogs and forums online describing how to fix the problem of duplicate or old entries in the “Open with…” contextual menu in Mac’s OS X Finder.  The problem with some of these sources is that the path listed is not always correct, rendering the ol’ copy-and-paste standby useless.  One easy way to handle this is with the locate command.

To rebuild the list of programs under the “Open with…” menu, from a Terminal shell, copy/type:

`locate lsregister` -kill -domain local -domain system -domain user

Note the ` [backward apostrophe] is the key shared with the ~ [tilde or "twiddle" in unixspeak].  This should not be run as the superuser, but rather as your own login.

This could potentially fail if you have more than one lsregister installed on your system, but that shouldn’t be the case with a default install.

You may need to logout and log back in for the changes to be seen.