Classic ASP Requires Chilkat v11.5.0+
Box: Download Binary Content into BinData

Run the reusable setup once per HttpCurl object, then select names and execute the operation. The setup is repeated here only to make this published example independently runnable. Download a small file into memory. For large files use the direct-to-disk example.
See the Box API guide for setup and the complete workflow.
Chilkat Classic ASP Downloads

Download Chilkat for Classic ASP
Classic ASP
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<%
success = 0

'  Requires Chilkat 11.5.0 or later and a previously unlocked Chilkat bundle.
'  See Global Unlock Sample.
'  Guide: Box API Guide.

success = 0

'  BEGIN ONE-TIME SETUP
'  This block is repeated so each published example can run on its own.
'  In an application, run the setup example once and pass the SAME curl object
'  to operation code below. Do not recreate it for every operation.
'  See Reusable Box HttpCurl Setup.
set curl = Server.CreateObject("Chilkat.HttpCurl")
curl.SetVar "access_token","BOX_ACCESS_TOKEN"
curl.SetVar "parent_name","/"
curl.SetVar "folder_name","images"
curl.SetVar "file_name","penguins.jpg"
curl.SetVar "destination_name","archive"
'  Box's fixed root ID is an implementation detail; callers supply names.
curl.SetVar "parent_id","0"
set setupCommand = Server.CreateObject("Chilkat.StringBuilder")

'  Register findParent; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findParent",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register findFolder; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/{{parent_id}}/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findFolder",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register findFile; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/{{folder_id}}/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findFile",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register findDestination; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/folders/0/items?limit=1000&fields=id,type,name"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("findDestination",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register getFileDetails; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/files/{{file_id}}?fields=id,sha1,file_version"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("getFileDetails",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Register getEnterprise; registration sends no request.
success = setupCommand.SetString("curl -X GET ""https://api.box.com/2.0/users/me?fields=enterprise"" -H ""Authorization: Bearer ACCESS_TOKEN""")
setupReplacements = setupCommand.Replace("ACCESS_TOKEN",curl.GetVar("access_token"))
success = curl.AddFunction("getEnterprise",setupCommand.GetAsString())
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  Initial name selections. AddOutput2 stores these WHERE values literally.
success = curl.AddOutput2("findParent","entries","name",curl.GetVar("parent_name"),1,"id","parent_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput2("findFolder","entries","name",curl.GetVar("folder_name"),1,"id","folder_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput2("findFile","entries","name",curl.GetVar("file_name"),1,"id","file_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput2("findDestination","entries","name",curl.GetVar("destination_name"),1,"id","destination_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput("getFileDetails","file_version.id","file_version_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput("getFileDetails","sha1","file_sha1")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

success = curl.AddOutput("getEnterprise","enterprise.id","enterprise_id")
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

'  END ONE-TIME SETUP
'  The name lookups below assume each listing fits in one page (1000 items).
'  Parent and destination names select root children; folder_name selects a child
'  of parent_name. "/" selects the root parent. These are not arbitrary paths.

'  BEGIN OPERATION -- keep the configured object when reusing it.
'  Inputs are names. Retain cached IDs when the selected names have not changed.
parentName = "/"
folderName = "images"
fileName = "penguins.jpg"
If ((curl.GetVar("parent_name") <> parentName) Or ((parentName = "/") And (curl.VarDefined("parent_id") = 0))) Then
    curl.SetVar "parent_name",parentName
    curl.ClearVar "parent_id"
    curl.ClearVar "folder_id"
    curl.ClearVar "file_id"
    curl.ClearVar "file_version_id"
    curl.ClearVar "file_sha1"
    If (parentName = "/") Then
        curl.SetVar "parent_id","0"
    Else
        success = curl.AddOutput2("findParent","entries","name",curl.GetVar("parent_name"),1,"id","parent_id")
        If (success <> 1) Then
            Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
            Response.End
        End If

    End If

End If

If (curl.GetVar("folder_name") <> folderName) Then
    curl.SetVar "folder_name",folderName
    curl.ClearVar "folder_id"
    curl.ClearVar "file_id"
    curl.ClearVar "file_version_id"
    curl.ClearVar "file_sha1"
    success = curl.AddOutput2("findFolder","entries","name",curl.GetVar("folder_name"),1,"id","folder_id")
    If (success <> 1) Then
        Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
        Response.End
    End If

End If

If (curl.GetVar("file_name") <> fileName) Then
    curl.SetVar "file_name",fileName
    curl.ClearVar "file_id"
    curl.ClearVar "file_version_id"
    curl.ClearVar "file_sha1"
    success = curl.AddOutput2("findFile","entries","name",curl.GetVar("file_name"),1,"id","file_id")
    If (success <> 1) Then
        Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
        Response.End
    End If

End If

curl.ClearTargetOutput "*"
set authorizedCommand1 = Server.CreateObject("Chilkat.StringBuilder")
success = authorizedCommand1.SetString("curl -X GET ""https://api.box.com/2.0/files/{{file_id}}/content"" -H ""Authorization: Bearer {{access_token}}"" -L")
headerReplacement1 = authorizedCommand1.Replace("{{access_token}}",curl.GetVar("access_token"))
success = curl.DoYourThing(authorizedCommand1.GetAsString())
If ((success <> 1) Or (curl.StatusCode <> 200)) Then
    Response.Write "<pre>" & Server.HTMLEncode( "Box request failed. HTTP status: " & curl.StatusCode) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( "Failure reason: " & curl.FailReason) & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( curl.ResponseBodyStr) & "</pre>"
    Response.End
End If

set data = Server.CreateObject("Chilkat.BinData")
success = curl.GetResponseBd(data)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( curl.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Downloaded bytes: " & data.NumBytes) & "</pre>"

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