Thanks for the ideas. Sadly I have none of these programs on my PC.
After a year of error-free Office 365 use, The dire message "We're sorry but this feature appears to be broken..."appeared this morning in Word. Up till now it had no problems at all operating alongside all my Add-Ins.
The only change I've made in the past two days is to add Project and Visio Professional 20132 to my hard drive, and activate them by Key (legacy of old TechNet!) rather than online.
Once Word starts to work, I started to get all sorts of dire macro warnings. In desperation (since I have work to do!) I selected the 'Enable All Macros' option. Dangerous, but the only way I can use the software.
On closing I am told Word cannot start the following convertors: RECOVR32, WPFT532, WPFT562, WPFT632.
Add-Ins include Babylon, Naturally Speaking, Omnipage Ultimate, and Acrobat PDF Maker (which I know was mentioned as a possible trouble-maker - but it has worked without a murmur until today).
Any thoughts?