Temporary citations appearing in Word document

I have a student who has created a Word document and associated bibliography that formatted correctly. However, when she tries to insert additional references to the document, they are appearing as temporary citations in the curly brackets. She has tried updating the bibliography but then gets the following error message: “CWYW could not connect to ENW. This may be due to a temporary internet or server error. Please try again.”, so the temporary citations are still there. She has tested this on different PC’s and at different times and has the same problems. She has also re-installed the CWYW plug-in.

Any ideas?

Many thanks