if photos is stalled when updating is it a problem to quit and restart

Stanley,

When you read through the article provided, you will find that an iMac can indeed have the SMC reset. I have quoted an excerpt for you in case you cannot find it.

"Desktop computers with the T2 chip

1. Shut down your Mac, then unplug the power cord.
2. Wait 15 seconds, then plug the power cord back in.
3. Wait 5 seconds, then press the power button to turn on your Mac."

"Desktop computers

1. Shut down your Mac, then unplug the power cord.
2. Wait 15 seconds, then plug the power cord back in.
3. Wait 5 seconds, then press the power button to turn on your Mac."

Cheers.

Hello Stanley,

Welcome to Apple Support Communities!

I understand from your question that your Photos application will not update. I can certainly help you with this!

I would start by restarting your computer and resetting the SMC.

How to reset the SMC of your Mac

I hope this is able to resolve your issue. If you have any more questions or this does not resolve your issue, please reach back out on the thread!

Cheers.