Secure forms 'unavailable' on submit??

[Cinquecento]

oh my....
I've a series of forms on a secure site running on Linux that submit to themselves for validation, inserting into mySql and then loading the next page.
Most of the time though the submitted pages are 'unavailable' - even though they are merely reloading. If I back up and re-type the form data and submit again, they work ok! Is it a script error? This never happens on other 'unsecure' pages on my server. I'm really stuck on this!

I've duplicated one of the forms under another name and submit to it from the original and it always works. So maybe I need to split my handling code for the form data and put it into a separate scripts?

Thanks for any help

Ian

[hand]

To deactivate any proxy-cache, code this four header instructions at the very beginning of your script:

header ("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // some gone date 
header ("Last-Modified: " . gmdate ("D, d M Y H:i:s") . " GMT");
header ("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1 
header ("Pragma: no-cache"); // HTTP/1.0 

To deactivate browser cache, insert following meta tag to your produced html codes

 
<META http-equiv="expires" content="0"> 

[Cinquecento]

Nope that didn't do it!

I think I'll have to strip out all the validation and processing scripts and run them on independent pages... it's the only thing that seems to work....

I don't know what causes this though - it's like the secure section of the server is caught 'napping' sometimes!

Ian