When I design a website I build and test using Firefox using Firebug. I have found that getting it right in Firefox is better than getting it working in IE7 then trying to iron out he differences. Once I am happy in Firefox I thne make some tweaks to get it rendering in Safari, IE7 and Opera.
Finally, I use conditional comments for IE6. The main issue with debugging for IE6 is that if you have IE7 then microsoft dont want you to have IE6 there too. This is where Multiple IE comes in very handy.
I normally install IE6 only. There are still a large portion of IE6 users out there. Public sector system admins probably don’t like change so all the workstations are stuck on IE6 with flash and javascript sometimes disabled.
If you have a server that allows you to connect via remote desktop connection then its work trying to debug from there. Most servers have IE6 still which can be a blessing. Servers admins dont like change much either.
If it seems like IE6 isnt working correctly then reset all the privicy, security and advanced settings. This helped me when IE6 wouldn’t show any images on a webpage
