Problems with registration in CSS Form Builder

I've built a simple three line registration form. First name, last name and email. I tweak the design and set up the mail send function. Test in DW CS5 and everything looks good. Upload to the server and the form shows the invalid msg. for each entry immediately after loading the page. I can't get rid of it!! I've wasted HOURS trying to get this fixed. Runs fine on my local machine in live view. Looks really stupid on the remote server.

Really tired of nothing being straight forward with anything in this suite of tools. I think I've read other places here..."I don't feel like I'm saving any time when I have to spend hours testing stuff that doesn't work the way you'd expect it to" and just doesn't.

Any help would be appreciated!