I have had a notification for an update on my Mac pro from Catalina to Ventura. It will not manually or automatically update. It will go through the whole process and then not dot it. I get a message that I cannot pair my iPhone without updating.

klmp1201 wrote:

Cannot update from Catalina to Ventura so I can pair my iPhone. Goes through the update then doesn’t. I have used very little space on my lap top. I have 250.69 GB of storage out of 448.89. I want to put my phone pics on lap top but won’t let me unless I update. I have tried every suggestion that I found and nothing seems to work. I have 2018 Mac Pro and iPhone XR.

Is your Catalina current ...macOS 10.15.7 (?)

You can try running the installer from a Safeboot and compare your results

How to use safe mode on your Mac - Apple Support

If you donwnloaded the installer it will be in your Applications folder "Install macOS Ventura.app" you can launch it from there like any other applications.

klmp1201 wrote:

Cannot update from Catalina to Ventura so I can pair my iPhone. Goes through the update then doesn’t. I have used very little space on my lap top. I have 250.69 GB of storage out of 448.89. I want to put my phone pics on lap top but won’t let me unless I update.

FWIW, the notice to update to connect your iPhone was a patch for Catalina.

See: If your Mac says that a software update is required to connect to iPhone or iPad

You could potentially download the Ventura osx from Apple, and then boot from that drive.