when doing the following- xmlhttp.Send(xmlSend);
on this object- var xmlhttp = new ActiveXObject("MsXml2.XmlHttp")

I sometimes get an error (after an IIS reset) that-
“The download of the specified resource has failed”
but sometimes it works.

I've read that it may be due to the version of MSXML that I'm using, but I've tried different versions- (MSXML2.XMLHTTP.6.0) and it doesnt seem to make a difference.

Any idea why this is happening?
(The xml I'm sending is always the same and is ok)