If your modem is recognized but won't connect, particularly after a Windows update (like the Fall Creators Update), you might be facing a known compatibility bug.
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Open Device Manager and verify that the "RNDIS interface" is present under Network adapters . Test Communication: If your modem is recognized but won't connect,
Some experts recommend keeping your PC's Wi-Fi active during installation to prevent Windows from incorrectly attaching a generic "Microsoft Modem" driver to the huawei e3531 draiver skachat