New information: the transformation is corrupted when there are tags "link" or "meta" in the XSL-file. So, if you can avoid using these tags, rendering will be Ok :-)

Interesting! How in the world did you find that out???

I'm not using link tags (just script tags), but I do have one meta tag:

Well, first of all I found that not all files were corrupted, so I suspected that the reason was in particular tag(s). Than I checked the differences in the files and eventually found the tags that cause the problem.

Just for test, try to remove lines with "meta" and "link" and see what happens...

Actually, this does not resolve the problem as we can't spare these tags.

I removed the meta tag, but still got garbage problems. Refreshing the page a few times occasionally made the problems go away, but usually the page would just show different glitches with each refresh.

Have you tried Firefox yet?

So, it seems that problem not only in mentioned tags. I don't install Firefox, because most of our users use IE. Therefore, for our company the only way to avoid the problem is to recomend our customers not to use Windows Vista

Are you generating static XHTML files from XML + XSL? Or are your customers viewing the XML + XSL directly in their browser (IE)?

If the former, then Firefox can be a good previewing/debugging tool, even if none of your customers uses it. I especially like Firefox's Web Developer Tools extension, which helps validate XHTML, CSS, and check for broken links.

In general we use IE+XML+XSLT, but we do have some pages generating HTMLs from XML/XSLT. Unfortunately, pages with the error are generated from XML on the user's side (via IE).

Out of curiosity, I just tried viewing one of the corrupt pages with CSS disabled. The corruption was still there.

Anything else we can try?