My late 2013 Mac Pro slows right down (taking 20-30 seconds to execute a mouse click) and hangs when opening apps - I've noticed this particularly with Excel 2011 and Preview. If I try to open a file in Excel using the File/open menu option, the system will freeze displaying a blank file dialogue box, forcing me to shut down the Mac by holding down the power button.
Have others experienced this? Any troubleshooting suggestions?
Try starting your Mac in Safe Mode. Restart your computer. Hold the Shift key when you hear the startup sound. Release the Shift key when you see the Apple logo appear. This starts your Mac in Safe Mode. Safe mode performs a directory check of your startup disk, and removes some cache data. After your Mac finishes starting up, restart your Mac normally (without holding the Shift key) and see if the issue is resolved.
Thanks for your reply.
None of the issues listed at the link you provided (macOS Sierra: If your Mac runs slowly) appear to be relevant. My Mac Pro has over 200GB of free disk space and 64GB of RAM and the activity monitor was not showing any unusual activity when the slow-down / hang issues occurred. I am not running any apps that require specific processors or graphics cards.
I have started up my Mac Pro in safe mode and the problem disappeared. I then restarted in normal mode and the problem did not initially recur. After a day of problem-free use of my Mac, the problem recurred immediately upon launching the Messages app from the dock. When I attempted to launch the Messages app, my Mac hung for about 25 seconds, then the app launched, but the part of the window where the messages should appear was blacked out. I tried to open a file in Excel 2011 and the Mac 'beachballed' while showing a blank open file dialogue window (as had been occurring previously).
My trackpad was still responsive and I was able to force quit Excel (it was not showing as non-responsive in the Force Quit menu, but I was still seeing a blank open file window and beachball). I then restarted my Mac in safe mode again. Once booted up in safe mode, I opened the Messages app, which still showed a black area where messages should appear. I opened Excel and was able to launch a file via the open file menu as normal.
I restarted my Mac in normal mode and all problems had again disappeared - Messages and Excel both worked normally.
I'd be grateful for any further thoughts on what might be happening, or advice on possible fixes. (I haven't yet tried setting up a 'test' user account, but will do this when the problem recurs.)
Start up from macOS Recovery by holding down Command (⌘)-R immediately after turning on or restarting your Mac. Release the keys when you see the Apple logo. Startup is complete when you see the utilities window.
Choose Reinstall macOS (or Reinstall OS X) from the utilities window, then follow the onscreen instructions.
This installs the latest version of macOS that was previously installed on your Mac.
How to reinstall macOS - Apple Support
Also, it might be a good idea to use Apple Diagnostics to check your Mac Pro's hardware. Take a look at this website for more information:
Using Apple Diagnostics - Apple Support
Take care!
Lots of users who have such type of slowdown problems happen to use Microsoft Office, i think Microsoft haven't updated their app suite to be Sierra compatible, and since MS Office installs and runs services and other stuff in the background even if main app isn't active, they might cause these slowdowns.
Visit MS Office support forums and look up possible compatibility problems.
Mac Pro freezes/hangs following install of Mac OS Sierra
