The icons on the top toolbar of my Mac keep flashing.

Try trashing this preference file and reboot.

HD > User > Library > Preferences > com.apple.systemuiserver.plist

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Try logging into another User account. Is it doing it there?

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OK, the problem is system-wide then. Have you installed any third-party apps that would have put an icon in the upper right of the menu bar? If so, try removing it.

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OK, boot from your install disc and reinstall your system.

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I've trashed the settings a couple of times. I've re-installed 10.6.2 twice, (after having many problems with the 10.6.3 version, I have given up). On other users it is NOT flashing.

Any other ideas ?

If the problem is not happening when logged into another User account, then the problem is isolated to your main User Library.

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OK, so what can I do to fix it ? Nothing else other than apple program icons there and no other recent programs. This only started today after I went back to 10.6.2 from 10.6.3 because I couldn't stand it any longer 😟

Here is an entry from the console log:

23/04/10 8:23:26 PM com.apple.launchd.peruser.502[165] (com.apple.SystemUIServer.agent[1954]) Job appears to have crashed: Segmentation fault
23/04/10 8:23:26 PM com.apple.launchd.peruser.502[165] (com.apple.SystemUIServer.agent) Throttling respawn: Will start in 7 seconds
23/04/10 8:23:26 PM ReportCrash[1953] Saved crash report for SystemUIServer[1954] version 1.6 (298.5) to /Users/ralph/Library/Logs/DiagnosticReports/SystemUIServer 2010-04-23-202326Ralphs-iMac.crash
23/04/10 8:23:36 PM SystemUIServer[1955] [111960] |ConflictManager|Warning| File lock for /Users/ralph/Library/Application Support/SyncServices/Local/conflicts was stolen at 2010-04-23 20:23:36 +1000 by SystemUIServer on host localhost with pid 1955, modifications to conflicts may be lost

OK, the logs point to the SystemUIServer like originally pointed out by trashing that preference file. When you reinstalled 10.6.2, did you try doing a "fresh" install (without adding and files or settings from a backup)?

Something does not seem right here.

|ConflictManager|Warning| File lock for /Users/ralph/Library/Application Support/SyncServices/Local/conflicts

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When I had the machine on and running under 10.6.3, I inserted the original Snow Leopard disk and followed the instructions for a standard install. Then I upgraded using the 10.6.2combo upgrade from my downloads folder. I then Repaired disk permissions, again, and have since also verified the disk (OK) and re-set the PRAM.

At this point, I suggest booting from your original install disc, reformatting the drive and install 10.6. THEN boot (before updating to 10.6.2 or adding any files from backup) and see if it's back to normal. If it is not, you have a hardware problem.

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