Hi Dragan

Thanks for your input, but that's where I started!

This has been the progression:

*!* oXMLHTTP = CREATEOBJECT("Microsoft.XMLHTTP")
*!* oXMLHTTP = CREATEOBJECT("MSXML2.XMLHTTP")
*!* oXMLHTTP = CREATEOBJECT("MSXML2.ServerXMLHTTP.3.0")
oXMLHTTP = CREATEOBJECT("MSXML2.ServerXMLHTTP.6.0")

I think the default goes for MSXML3. I was getting errors like these in the beginning:

OLE IDispatch exception code 0 from msxml3.dll: Not enough storage is available to complete this operation.
OLE IDispatch exception code 0 from msxml3.dll: The system cannot locate the resource specified.
OLE IDispatch exception code 0 from msxml3.dll: The operation timed out

I thought I had a resolution by running the code on another server, but that appears to have worked only once (???) and now I get the same error running the exe anywhere other than my desktop PC:

OLE error code 0x8007045a: A dynamic link library (DLL) initialization routine failed

This makes Antonio's suggestion of a reinstall of MSXML6 seem unlikely to succeed. Surely it's not a problem with a corrupted DLL on every machine except mine?! I'm wondering whether it's using a resource that's part of the VFP9 IDE install...?

Thanks

Graham