Determining the Browser Operating Environment

I would like to log in to a service using Python from the program.
However, it is skipped to the page "Operating environment is not covered".
The same thing happens when you disguise the User-Agent.
Is there anything else that determines the environment other than the User-Agent?
All necessary information is sent via POST.
By the way, the address to which the request will be sent is a .jsp file.
The data I am sending is Userid, password, UserId is an 8 digit number, and password is an 8 alphanumeric character.
By the way, I don't know how this service is implemented.
Status returns 200 OK.

import urllib.request
import urllib.parse

post_data={"UserId":12345678, "Password": "password"}
encoded_data=urllib.parse.urlencode(post_data).encode()
requ=urllib.request.Request("http://example.com/login", 
                             encoded_data,
                             headers={"User-Agent": "Mozilla/5.0 (Windows NT 6.3; Trident/7.0; rv:11.0)like Gecko"})
res=urllib.request.urlopen(req)
res_read=res.read().decode("shift-jis")#res_read contains the character "Operational Environment Not Included".

The operating environment required is as follows:

Windows Vista SP2 or higher
·Internet Explorer 7
·Internet Explorer 8
·Internet Explorer 9
·Google Chrome

Windows 7 ·Internet Explorer 8
·Internet Explorer 9
·Internet Explorer 10
·Internet Explorer 11
·Google Chrome

Windows 8 (Desktop UI)
·Internet Explorer 10

Windows 8.1 (Desktop UI)
·Internet Explorer 11

Mac OS X 10.6 ·Safari 5.1.7

Mac OS X 10.7 ·Safari 5.1.7

python http jsp

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