Thank you all for helping me to overcome my HTML problem. I followed Howard Kaplan's procedure which allowed me to find the single line where the problem lay amongst my many pages . The code in this rogue line looked like code which the preview function was accepting elsewhere - perhaps there was an odd extra space in some place . I experimented by switching bits of code about and trying the resulting lines in the preview function and eventually found something that was accepted. I then inserted that and posted all the pages successfully Thank you all so much XX