Error: InfoPath cannot load the view... unsupported HTML such as framesThe following HTML tag is not supported:'comment'

It may have a corrupted form.

Infopath forms (in 2007 anyway) are actually just Microsoft CAB files. Youcan rename a form from .xsn to .cab and then open it using any aplicationthat understands cab files.

There are a number of files in each CAB file, but the ones you areinterested in are probably the *.XSL (there is one for each InfoPath "View"plus some extras) and the manifest.xsf file which is like the "table ofcontents".WARNING!!! DANGER WILL ROBINSON!!! etc etcThis isn't for the faint-of-heart, but you did say you were desperate...
You may have to run through a combination of:

1. Renaming the .XSN to .CAB
2. Expanding the .CAB file
3. Hacking either the individual xsl views and/or the manifest.xsf to removethe offending view(s)
4. Repacking the CAB file
5. Renaming back to .XSN
6. Open in Infopath, hope error is gone

This has only happened to me once - I ended up having to delete theoffending view and recreate it. To find out which view was broken, I had todelete each view, reopen, repeat until I found out which of the views wasbroken. Worked for me (we had about 30 very complex views) and saved a wholelot of time.

Repacking the extracted files of infopath back to .xsn

Right-click on the manifest.xsf, select Design, save as xsn.