I can see the form Here OK, and if I browse directly to the thankyou.php page (in the same directory where it should normally be) it shows up here just fine. So the physical paths seem to be OK, at least for those two files.
Have you checked to see if all the required other required CFSP folders and their contents are contained in the same ContactForm/ remote folder? You should see:
as well as your contactus.php and thankyou.php files
I ask this because there is no client-side (Spry) validation happening when I click in and out of the fields; or errors from the server-side code when I do an incomplete submit. Did you remove the validation(s)? If not, then there may be a path problem with the Spry (and perhaps the other files/folders). If they are there, check that the file and folder names are entered with the correct case, case-sensitivity errors would report the files as missing.
This form was working fine at one time, if I remember correctly; - is it on the same server as before? Are they the same pages?
When I type the following in to the address bar:
I should get a blank white page, that would indicate that the 'mail.php' file is present, but I get a 'not found' message.
I am not finding the WA_Globals/WA_Globals.php in the expected location either.
Check for the presence and case of the required files and folders, - all in the ContactForm folder, and see if anything is amiss there.
You have probably tested all of this already, but a single typo or case issue could be the cause of the problem.
If you did remove all the validation from the form, perhaps re-inserting it would take us a step forward in the diagnosis.
Also I see in the Head of your document,
Note the: 'cfsp/SpryAssets' in each one, - the cfsp/ should not be there. So check the paths of the php includes at the top of your page too.