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There is a limit on posted message data set by the receiving server. Or is 
the error occurring when you try to convert the data to Base 64? 
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The error message appread right during the binary value is assign to 
.nodeTypedValue. The "< file in binary with 70MB >" is a function where it 
converts a 70MB+ .pdf file (or any file that 70MB+) to byte() array. The 
function is processed smoothly


------------------------
What are you uploading to? 
Are you using XmlHttp? 
Why would you want to stuff 70MB of data into an XML file? 
70MB binary = 93MB base64. 
What component is actually throwing the error, the client side code or the 
server. 
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These are the actual codes:-
****************************************
Dim returnDom As New DOMDocument
Set objValue2 = returnDom.createElement("BinaryData")
objValue2.dataType = "bin.base64"
objValue2.nodeTypedValue = GlobalFunc_GetFileBinaryContent(sOpenDocFile)
****************************************
-I'm using DOMDocument
-I want to use MSXML to upload a file from client vb6 to a website server, 
where the website will store the file as binary into SQL Server
-The component throws the error at client side

Thanks a lot for the replies. hope my info can help.