Ouch, sorry. It does sound like reverting to your Mojave backup might be the better part of valor for now.
Another reason to hold off on upgrading to Catalina: developer Michael Tsai has received numerous complaints of Mail-related data loss after upgrading.
https://mjtsai.com/blog/2019/10/11/mail-data-loss-in-macos-10-15/
I upgraded my late 2013 MacBook Pro Retina. It downloaded and restarted in 10 minutes, so I thought it was going to be fast. But it took 2:45 hours to finish up. For a very long time it was just sitting in place. I read above that some people gave up at that point, but I knew from past experience to wait it out, and it finally finished up just fine.
Catalina 10.15.1 Beta 1 is already out. I’m downloading it right now.
I got a message from CERT says Apple had released security fixes for the Mac, so I went ahead and installed them. That turned out to be Catalina 10.5.
So far I have had only one problem – Xcode install failed. The message was:
Unable to Download App
“Xcode” could not be installed. Please try again later.
First, make sure you delete any current copy of Xcode that you have. If there is a copy on any external drive, unmounted it. Then try the App Store again.
Generally I’m pleased by Catalina, I like the System drive being partitioned. But one thing: booting into single user mode (Command-S startup) and running FSCK fails — naturally, as the System partition is now write protected. An issue I think!
OK. Update. Thursday after my time online with Apple Support I had been promised a response from Engineering. I called this morning, did not have to wait for an advisor and got right to it. She looked up my case and said that Engineering had responded late last night. She had me open Keychain Access and mess with one of the login files, restart and Bingo! I’m just about all the way back!
The only problem that I still have is that some of my email has disappeared. I’ve got the Sender and the Header but the body is gone. This is problematic because some of these emails had attachments and info I really wanted to save.
Does anyone know if I can retrieve individual emails from Time Machine?
Otherwise I’m very happy with the support I got from Apple. I shouldn’t have had the problem to begin with, but all in all I’m doing very well with very little inconvenience.
No surprise, there are always issues with Adobe apps with each upgrade of macOS… grumbles
Are the problematic messages in “On My Mac?”
Thank you,
David
No. Most of them are in the Inboxes. The ones I’ve noticed (because I care about them) are the ones that have been flagged.
BTW. I’m UNABLE to retrieve them from Time Machine. When I load Time Machine with Mail up front, Mail crashes every time. Apple support is working on this.
Are any of the problem messages in On My Mac?
If not, what happens if you move any of them there?
One other issue I don’t think has been mentioned: after a completely painless update to Catalina on 2013 11" and 2017 13" MacBook Airs, in both Macs the System Management Controller which manages power was munged – batteries went down to zero overnight on Sleep.
Went to Recovery (Command-R startup) and disabled firmware password.
A SMC reset (power down, power in; hold shift-control-option-power for 10 seconds) plus a NVRAM reset (command-option-P-R startup) fixed the battery drain issue completely – both Macs at 100% after an overnight sleep this morning. One should do these after any OS update of course – I’d been careless 
Bill Stanford
As I have indicated on the thread about problems with Catalina Mail, I recommend Mail Steward for creating a backup of your emails that is seperate from the OS email data. I can go back and open attachments from more than a decade ago.
Probably won’t help those with current email problems (but it might be worth a try archiving current emails and see if Mail Steward gets around the corrupted data)
I don’t get the upgrade notification, but the red counter in Sys Prefs irritates me quite a lot. Is there a way to get rid of this, except of course upgrading?
Sorry for this post, did find the answer in this discussion. Adam, thanks!
My upgrade experience is terrible. The actual procedure went well, but then my Bluetooth Sony WH-CH500 headphones started to act chobby. I was trying to fix that all day, I read other people were having that problem, ending up on reverting back to Mojave. Don’t upgrade unless you explicitly know what you need from the Catalina. It’s just not worth it
I’m definitely waiting to update to Catalina. I still can not find ANY info on what happens if your default location for iTunes is an external hard drive. Is Catalina going to try and pull all the content back to the Mac HD? With 1.5 TB of iTunes content on the external drive there is not enough room on the Fusion drive. The Installer is not, I guess, going to Partition the external drive to break up iTunes. SO does that mean I should separate Music and Movies/TV first while still running Mojave? Then Catalina makes the change? NOT!
Sheesh! I don’t know what to do? Except wait.
Bummed out old rocker 
in the Shenandoah valley.
I don’t know what it does on conversion.
I do know you can point the Music App to your iTunes library on an external drive. The music library screens look the same in Catalina as they djo in Mojave.
Norm Gilbert
Retired
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Skype: fogcitynative
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