Custom keyboard crashes Microsoft Word on Mac

Try restarting the computer then retest. Unless a keyboard is faulty or you have installed something like third party:

• Antivirus
• Cleaning
• Security
• VPN
• Maintenance

apps the keyboard does not have the ability to create issues. I'd strongly suggest the following:

It will help us get a good idea of what is causing your problem if you provide a report of your system, that way we do not have to play 20 questions with you. The report we are requesting does NOT provide any personal information and is extremely safe to use. Please navigate to www.Etrecheck.com and download the free version of EtreCheck. Once you have you downloaded the app and installed it, please run the report and save it. This report will help us get a good idea what has been installed on your system and help us be able to diagnose what may be wrong.

When you have your report, you can attach it when you reply to this message and we can then review it and help you determine what is needed to get your system running well again. 

For instructions on how to download your EtreCheck report and attach it to your reply to this message please click How to use the Add Text Feature When Post… - Apple Community It is helpful to us if you download the report to your Desktop.

jemiljan wrote:

@TomGewecke made a terrific keyboard for me several years ago that I constantly use. However, now it crashes MS Word! ABC Extended Keystrokes- Why do they only… - Apple Community Help!

Does the ABC Ext Umlaut Below input source still work with Apple apps like Safari, Mail, Notes, Messages, TextEdit, Pages?

Exactly what version of Word are you using?

PS On my Word 16.99.2 in Sonoma, that keyboard still works ok. I have it installed in Home/Library/Keyboard Layouts (not in Library/Keyboard Layouts) in case that makes a difference.