How to Fix OS X Lion 10.7.3 CUI Bug

A strange error showing a message that reads “CUI” causing applications to crash on launch has been discovered in OS X 10.7.3 Lion. Fixing the issue is complicated, though not impossible, and Apple is already on the case for a future software update.

Many users who installed OS X 10.7.3 on launch day became very disappointed to see that the software update, which promised a lot of fixes, actually made their life harder.

Particularly, OS X 10.7.3 caused their applications to crash on launch. And while there is a fix that involves downloading and installing the Combo OS X 10.7.3 update, you can’t obtain it if your web browser keeps crashing, now can you?

Some users have been able to start their computer in FireWire Target mode, connecting it to another Mac, download the Combo Updater and then install it to the affected Mac over FireWire. It’s a hassle, but most people seem to have resolved their issues using this method.

An alternative solution, if you don’t have another Mac at hand, involves some Terminal work, as detailed in this 9to5mac post.

Those who haven’t yet updated to 10.7.3 can sit still or - if they really need the fixes and enhancements delivered in this update - download the Combo updater located at this here link:

Download OS X 10.7.3 Combo (Free)

After learning of the bug (and perhaps several others) Apple sent out an email to a group that’s actively testing OS X Lion 10.7.3. The message said:

“We would like to know if you have experienced an issue after updating to 10.7.3 characterized by the following: Applications crash or quit on launch, The term “CUI” and other graphic anomalies appear in dialogs and windows. If you have encountered this issue please submit a bug report. Be sure to include the following with your report: Install logs, system logs, a full System Report.”

A new software update should be in the works as you are reading these lines.

Apple generally deals with these types of issues by re-launching the incremental release once again, assigning it a different build number.