Unable to install 10.15.0

[donl1150]

Ok folks, here is what is going on. I am trying to upgrade from Mohave to Catalina. So I use Carbon Copy Cloner to clone my internal drive to an external drive. Perfect. Everything works great. Got a good backup ready to go. I erase the internal drive and reformat to make sure it is APFS. Still ok. I download and install Catalina to the internal drive. Still in good shape....Catalina installed and the internal now ready to accept CCC to transfer things back.

Now things go wrong. CCC transfers everything back, including Mohave. So logically, I try to do an update to Catalina. I get an error message that says I need to install 10.15.0 in order to do that. The assumption is once that is installed, then likely more upgrade steps to get to Catalina. Problem is I can't get 10.15.0 installed. Had Apple support link in to my machine and we spent 2 hours trying to accomplish. They can'f figure it out either.

So maybe another idea is if CCC can some restore everything BUT Mohave but I don't know if that is possible either. I have a ticket in for them on that possibility but not heard back.

Anyone have some ideas?

 

[chrfr]

Ok folks, here is what is going on. I am trying to upgrade from Mohave to Catalina. So I use Carbon Copy Cloner to clone my internal drive to an external drive. Perfect. Everything works great. Got a good backup ready to go. I erase the internal drive and reformat to make sure it is APFS. Still ok. I download and install Catalina to the internal drive. Still in good shape....Catalina installed and the internal now ready to accept CCC to transfer things back.

Now things go wrong. CCC transfers everything back, including Mohave. So logically, I try to do an update to Catalina. I get an error message that says I need to install 10.15.0 in order to do that. The assumption is once that is installed, then likely more upgrade steps to get to Catalina. Problem is I can't get 10.15.0 installed. Had Apple support link in to my machine and we spent 2 hours trying to accomplish. They can'f figure it out either.

So maybe another idea is if CCC can some restore everything BUT Mohave but I don't know if that is possible either. I have a ticket in for them on that possibility but not heard back.

Anyone have some ideas?

Download a fresh copy of Catalina from the App Store and try again. The current installer will include 10.15.7 and save you some update steps. Follow the link on this page to get Catalina: https://support.apple.com/en-us/HT211683
Depending on what model computer you have, you may also be able to get Catalina by starting up in internet recovery (hold command-option-r as the computer starts up.)
CCC is working exactly as expected. When you restore your backup to the disk, CCC tells you that it's erasing the destination disk to do it. After Catalina is installed, when the computer prompts you to migrate data, just point it to your backup, and then Migration Assistant will just copy your settings and files but leave the newer operating system in place.

 

[glenthompson]

As mentioned you can use Migration Assistant to copy your old stuff over to the new install. If you want to a completely fresh install you can create your users on the new install and then re-install all your apps and then use finder to copy over the user documents. I did that when I upgraded to Catalina so that I could make sure I had no 32 bit apps remaining.

Another option would be to just upgrade your Mojave installation to Catalina.