A family of Microsoft word processing software products for creating web, email, and print documents.
I think the "Stick with .docx" idea would work if I was planning to start a new file. I would always write and save it in .docx first, then do Save As Web Page. If I later wanted to add or edit, I should do it in the docx file and save it in that format first, effectively keeping it as the master file, then again Save As Web Page to replace the old htm file. In other words, I shouldn't open the htm file in Word and expect to be able to edit it then re-save it in that format. Working directly in the htm file and saving it 'as is' (either as a docx file or as a web page) seems to be where the problems come in.
This still shouldn't happen, even when done that way, if Word actually allows an htm file to be opened and edited.
Note to self for future ... use docx as the Master and do any later editing directly in there. Presumably then the links etc wouldn't be "internally tinkered with".
Just to add further to the list of glitches (even in the older Word 2008) ... when a file contains a picture (e.g. jpg) which has been inserted amongst the text then Saved as a Web Page, it appears ok later in a browser. But then if further editing is done, the picture may or may not still appear in the htm opened in Word! If it doesn't appear (and this only seems to be a random thing) then the (empty) space where the pic was is still there, and clicking in the area shows a black frame where the picture should be. So I have to delete the empty frame and again do Insert/Photo/Picture from File where the original one was.
Think I should have just taken a deep breath 'way back' and bought a dedicated web writing program in the first place!
Thanks again Peter for your efforts!
Paul