Why is Microsoft Excel 2016 so slow when Internet connected
Solution 1:
When I had a similar problem, disabling dropbox integration (I never realized I had enabled it) made a huge difference in performance, especially for otherwise trivial things in Office/Excel like copy and paste (which had become unbearable).
System Preferences->Security & Privacy->Privacy Tab->"Allow the apps below to control your computer" (dropbox was checked, I unchecked it). Not sure exactly what functionality this took away from dropbox, but it still syncs folders fine, which is all I used it for anyway.
(I know this is thread is over a year old, but it's one of the first results in Google so I'm adding this for all the others who come along in hopes it may help them).
Solution 2:
I add excel to Accessibility, and it works fine for me, also I don't have Dropbox installed on my mac
Solution 3:
I believe there is an out of control process causing this that needs to be force quit to get performance back to normal.
Here are my online findings on the topic:
- https://www.reddit.com/r/mac/comments/40b2in/why_is_office_2016_so_goddamned_slow_and_how_to/
- http://answers.microsoft.com/en-us/mac/forum/macoffice2016-macexcel/microsoft-excel-for-mac-is-so-slow/b6a1ff39-ec33-4d20-8093-e0cbe4abf902
- http://answers.microsoft.com/en-us/mac/forum/macoffice2016-macexcel/excel-2016-painfully-slow-while-moving-from-one/53463e80-ade9-43fb-96bd-904a5db3e514?page=3
The comments hint towards too many "open ports". Force quitting the excel process via activity monitor with the most ports seems to do the job. I suspect this is a registration connection issue..
Office tries to constantly connect home and check that the product is registered. If you are offline and then go online then the issue occurs. I'm guessing these open ports are in reference to internet connections to a registration server.
Solution 4:
Select "normal view" instead of "page view". This is located in the lower right hand bar. Page view seems to have issues and be very slow.
Solution 5:
I had the same problem with Office 2016 & MacOs High Sierra.
it was nearly 20 second to open Excel, and 15 second to open Word. Then I did:
System Preferences > Security & Privacy > Privacy Tab > Accessibility
I removed Dropbox from there, then opened Excel (or Word). When it ask to you for permission Dropbox, said No & Do not ask again.
Its now 3 seconds for Word and 5 second for Excel. Not the best but better.