Catalina 10.15.5 Update -- "Contacts" Does Not Function

Start with this & let us know...

Safe Boot from the HD, (holding Shift key down at startup), does the problem occur in Safe Mode?

Safe mode attempts to repair Disks & clears lots of caches, so if Safe Mode works try again in regular boot.

Have you run any "cleaning", "optimizing", "speed-up" or anti-virus apps on your Mac?

Download and apply the macOS Catalina 10.15.6 Combo Update  and see if that fixes the problem.

If not log into another admin user account, Set up users, guests, and groups on Mac,  and see if the problem persists. (This tells us if the problem is limited to your user account or is system wide).

If still around boot into Safe Mode (How to use safe mode on your Mac - Apple Support) by booting with the Shift key held down and check there to see if the problem persists.  Reboot normally and test again.

NOTE: Safe Mode boot can take up to 10 minutes as it's doing some system cache cleaning, volume verifying and directory repairing. 

Since the problem is limited to your user account download and run Etrecheck. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

Copy the report

and use the Add Text button to include the report in your reply. How to use the Add Text Feature When Posting Large Amounts of Text, i.e. an Etrecheck Report

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the Etrecheck's Privacy preference pane so that it can get additional information from the Console and log files for the report:

Also click and read the About info to further permit full disk access.

Then we can examine the report and see if we can determine what might be causing the problem.

Thanks Old Toad for your quick reply. I followed your suggestions and here are the outcomes:

Have you run any "cleaning", "optimizing", "speed-up" or anti-virus apps on your Mac? no; other than EtreCheck

Download and apply the macOS Catalina 10.15.6 Combo Update  and see if that fixes the problem. Did that but did not help.

If not log into another admin user account, Set up users, guests, and groups on Mac,  and see if the problem persists. (This tells us if the problem is limited to your user account or is system wide). Worked in the other admin account--so it appears it is limited to my account.

If still around boot into Safe Mode (How to use safe mode on your Mac - Apple Support) by booting with the Shift key held down and check there to see if the problem persists.  Reboot normally and test again. Did not work in Safe Mode

I did, however, change the default account for my contacts and found that the problem was resolved. Challenge is that my original default account is where 70+% of my email traffic goes.

Thanks so much for your help thus far. Any thoughts on how I might address this problem further?

You're got a lot apps crashing but Contacts is not one of them. The worst is mds which is associated with Spotlight. Here's what I would do:

1 = boot into the Recovery volume (boot with the Command + R keys held down), select Disk Utility and run First Aid on the boot drive. If you get any errors repeat until there are not errors. Then reboot normally.

2 - reindex all hard drives for Spotlight: How to rebuild the Spotlight index on your Mac - Apple Support  

3 - You're having some memory issues.

  Swap Used: 1.51 GB

That shouldn't be happening with 16 GB of RAM. Limit the number of apps open at the same time. Know that Google Chrome is a known resource hog. If you don't like Safari give Firefox a try. It's much more secure than Chrome.

4 - limit the number of apps you have launching at boot and running in the background all day. Make sure you have the latest version of them all. Dropbox has been crashing a lot. You might uninstall it completely and reinstall a newly download copy.

5 - You have some Seagate software installed for your Seagate EHD which is formatted HSF+. You don't need that software to manage the drive and it only gets in the way of the system software. Uninstall it accord to the developer's instructions.

Run for a bit and see if there's any improvement.

Hi. I have a similar problem. In my case, Contacts will open and work normally until I try to add a new contact. I can typically complete two to five fields after which the app "beachballs" and then kills of the new contact in process. What I have found is a number of "No Name" contacts (roughly equal to the number of new entries I have tried to input) that have been created but contain no data. If I open one of the "No Name" contacts I can "edit" it by inputting all the data i would for a new contact and thereby create a contact. I do not know if this is a bug many people are encountering or if this is unique to my MacBook.

MacBook Pro (13-inch, 2017

Catalina 10.15.5

3.5 GHz Dual-Core Intel Core i7

16 GB 2133 MHz LPDDR3

Thanks again Old Toad. I have attached the EtreCheck Report as additional text.

Any luck?

OK, good work, take care my friend! :)

Thank you! I will implement your suggestions and let things go for a few days to see what happens. Really appreciate you sharing your knowledge with me.