The OS X 10.6.3 update that was released Monday appears to be without any major problems. Numerous people have had success with the update and some have reported much improved features such as graphics performance with OpenGL applications seeming much faster; however, as with any update, there are bound to be those who have problems and a few people have contacted us and posted on the Apple message boards regarding various issues they are experiencing.
Third-party application problems
A couple of people have had issues with getting some application suites up and running after the update. Some have reported that Adobe CS3 and Font Explorer X will not open, and others have had problems with programs either crashing or running slowly.
These problems may stem from an incompatibility with the update; however, if so, then most users of the programs would experience similar issues. Since these reports appear to be more isolated issues, it suggests the problem is more likely because of faults with specific application settings and setups. These include incompatibilities with third-party plug-ins for the programs, or corruption in preference and other resource files.
To fix these problems, first try running the programs without plug-ins, either installed or enabled, the locations of which will be unique for each program so read the manual, and then try deleting the preference and other settings files for the program. These can usually be found in the /username/Library/Preferences/ folder, but also may be in others such as /username/Library/APPNAME/ or /username/Library/Application Support/APPNAME/. Clear the files in these folders that pertain to the problematic application, and try running the program again. If the problems still persist, try removing and reinstalling the application.
Apple-supplied application issues
A couple of people have had problems with programs that Apple supplies with the OS, such as iCal or Mail, where the interface may appear to have glitches, or the application may not behave as expected by running slowly or crashing. If this is the case, the first method for fixing would be to rerun the installation by downloading and applying the "Combo" updater. Doing this will ensure all files changed since the initial 10.6.0 version are refreshed.
If the combo updater does not fix the problems, as with third-party application issues, try locating and removing preference files associated with the program. You can test out the program in another user account to see if user settings are the main problem.
Kernel Panics and OS problems
A few people have found that after updating their systems have started to crash with kernel panics, especially when booting. This may be caused by incompatibilities with external devices, so try rebooting into Safe Mode with the devices unplugged to see if the panics continue. If it does, you can try running the Combo updater again when booted into Safe Mode, or, more preferably, restore your system to a backup and reapply the combo updater from there.
To do this, boot from the Snow Leopard DVD and choose the option to restore from the "Utilities" menu, select your previous Time Machine backup and allow the system to fully restore the previous installation. If you have a hard-drive clone, attach it and boot with the Option key held, select the cloned drive, and boot to it. Then use the cloning utility to clone the drive back to the main boot volume, select that volume as the boot drive (in the Startup Disk system preferences), and restart.
Once your backup is restored, download the 10.6.3 Combo update (available here), reboot into Safe Mode, run general maintenance routines (i.e., permissions fixes and hard-drive checks--the items mentioned in ), and run the OS updater again. Do this with peripheral devices disconnected, and when the update is fully applied, reboot several times and otherwise check the installation before plugging in peripherals again.