MS Word was working fine last night. This morning, it is going incredibly slow. I clicked the X to close the search dialog. That took about a minute to close. I've tried clicking on words in the text and it is not really working. I can't imagine what changed. I used Malwarebytes to look for viruses and it didn't find any. Any suggestions of what to try? I'm working against a deadline and I can't have this for a 70-page document. I've closed all my browsers. Speed in other apps, including Firefox, is fine. It is only Word that has a problem. Thanks.

Without knowing what is in your document I will suggest steps I would take to improve performance.
1. Change the view to Draft - this frees up resources as Word doesn't have to continually work on pagination
2. Disable addins which may be causing slow downs
3. Remove all section breaks from the document and reset the headers and footers. If the speed improves, re-add section breaks where they are NEEDED

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Andrew Lockton
Chrysalis Design, Melbourne Australia

I solved this. I had just installed grammarly. As soon as I uninstalled it, Word worked as expected.

I think we conclusively conclude: "There is nothing that will slow down Word like Grammerly."
Even after I asked them how to uninstall it for Word it still shows up and I have to manually stop it. Absolutely terrible, like a leach.

Sometimes a simple reboot can fix temporary software problems.
Do you have the latest version of MS Word 2019 installed? You can check for updates by opening the File menu, selecting Details (or Help in older versions), and clicking the Update button. Try disabling add-ons: There may be some add-on or plugin that is interfering with Word. Try disabling all add-ons temporarily and see if you can continue working without any slowdowns.