System preferences icons disappeared.

dpogarjr wrote:

I am using Catalina 10.15.5 and went to opened my system preferences and there are no icons except flash player.

To trouble shoot further you can:

—Try a SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc. Login and test. Reboot and test as caches get rebuilt.

In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc hampering smooth operation, however a reboot will put it back to normal mode.

This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.

—Test issue in another user (or guest user) account  https://support.apple.com/en-us/HT204443

This will tell you if it a universal issue or isolated to your user/admin account. 

You can always reinstall the combo update on top of your existing macOS to sort anomalies

Combo update macOS 10.15.5 https://support.apple.com/kb/DL2040?locale=en_US

dpogarjr wrote:

Combo update macOS 10.15.5 https://support.apple.com/kb/DL2040?locale=en_US

This resolved the issue.

Thanks for report dpogarjr . This will help others as well as refine our tech support recommendations.

good computing !

I would first shut down the computer. Then restart. If the problem persists, create a new user and see if the problem is still there. If the new user does not present this issue, then some troubleshooting within your own user account is called for.

If all users have the problem, make sure you have a backup of all files.

Reboot the computer into Safe Mode (hold shift key while rebooting), it may take a number of minutes to boot in this manner. After booting, then restart, check for the problem.

If the problem persists, boot into Recovery (hold command-R while booting) and select Disk Utility. Run the first aid disk check/repair on the disk. Restart and see if the problem persists. If it does, then boot into Recovery again and select the option to reinstall the operating system WITHOUT erasing the disk. Erasing the disk would mean all your files are gone so don't select that option.

When you want to enter safe mode you have to hold down the shift key as soon as it turns on not when you see the log in screen. Safe boot should be in the corner of the log in screen