VBA WINHTTP POST - Required MultipartFile parameter 'file' is not present

[JasperD]

Hi all,

I am posting a WinHTTP POST request to an internal company site, and get an error HTTP responsetext saying "Required MultipartFile parameter 'file' is not present". I don't understand why.
Code so far (internal site obfuscated):

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The structure of the request and body was taken directly from the actual request, so there is nothing weird on that.
I added the following bit in order to try and fix the issue, but it doesn't help (it doesn't seem to hurt either).

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I've also replaced Chr(10) with Chr(13) -- essentially trying both VbNewLine and VbCrLF, but it doesn't matter either.

Please help!

[CK76]

Best bet is to use Developer Tool on browser of your choice and trace what request parameters are sent with POST request.
Make sure to check un-parsed raw string that's sent.

This will give you exact query parameter string you need to send.

[JasperD]

Did just that and it looks identical (the body) - I also tried to add all the requestheaders as below - didn't help.
In my experience, missing requestheaders would also give a different error.

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[CK76]

Hmm, try replacing CHR(10) with '%0D%0A' which is URL encoded vbNewLine/vbCrLf.

Also, see link for more details on multipart/form-data
https://www.w3.org/TR/html401/intera...html#h-17.13.4

[JasperD]

Tried to no avail - also read your link (thanks!), but don't see anything wrong.
Let me try and get the raw string from another browser...

[JasperD]

I figured it out -- the bit with the data (for x part) needed Chr(10), the rest needed Chr(13) + Chr(10).
You can't make this sh.t up...

Thanks for the help CK76 - much appreciated!

[CK76]

Dang, that's an odd set up. Glad you got it solved though