Yes, FrontPage is not exactly the newest web editor out there, but if you are still using it or maybe you have switched to Expression Web 4 (the updated FrontPage), you would probably still see this same problem.
The problem is when you edit a web page, whether it is .asp, .htm, or .html, outside of FrontPage, maybe you change the code with notepad or notepad++ (like I use), regardless, when you or someone else opens the site in FrontPage, the code on your perfectly formatted page goes whacko. FrontPage throws in some extra <p>, moves code or just rearranges lines. I have finally found the solution, and really want to save myself the frustration of finding this solution again. So I am posting it here for the world to see!
Do a search in your site for the files named the same as your page. For example if your page is called “mynewpage.htm” do a search for “mynewpage.htm” (without the quotes). MAKE SURE to search hidden folders and files. You will see duplicate files that reside in _vit_cnr, _vti_cnf1, or _vti_pvt. Those duplicate files are why FrontPage is “fixing” your code.
DISCLAIMER: BACK UP YOUR SITE BEFORE TRYING THIS!
1. Make sure FrontPage is closed.
2. Make all your changes to the page with notepad or whatever you use.
3. Save your file.
4. Delete the duplicate files out of the hidden folders
5. Open FrontPage and it will no longer change your code back.
It will still might add all the typical garbage back, but mine didnt.
Enjoy!