How to fix modem error 633

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Updated onOctober 4, 2023

updated onOctober 4, 2023

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Many users who recently upgraded to the Creators Update have encountered internet connection issues with one of the most common errors reported beingmodemerror633.

Thiserrorindicates that yourmodemis not configured properly.

Error 633 affects allmodemmodel and isn’t connected to any specific device. Here’s how one userdescribesthis issue:

My zte ac 2766CDMA USBmodemnot working after i updated to Windows 10 creator update it is givingerror633 please help me it is only Internet connection I have.

Thiserrormay occur if the communication port used by yourmodemhas been reserved by another software program. Error 633 also occurs when users set up multiple internet connections.

Iferror633 is blocking your Internet connection, follow the troubleshooting steps listed below.

How do I fix Error 633: The modem is already in use or not configured properly?

Solution 1 – Run the built-in troubleshooter

The first step is a rather simple one. With Windows 10, Microsoft sorted out a bit messy troubleshooting options.

Now there’s the unified menu within Settings where all troubleshooting tools reside. You can find it in Settings, under the Update & Security section.

Among others, there are Network Adapter Troubleshooter and Internet Connections Troubleshooter which should come in handy when errors like this occur.

Follow these steps to run the Network Adapter Troubleshooter:

Solution 2 – Update your modem drivers

Download and install the latest drivers for yourmodemfrom the manufacturer’s website.

You can also use the Device Manager to update your drivers:

Solution 3 – Uninstall and reinstall your modem drivers

If updating yourmodem‘s drivers didn’t eliminateerror633, try uninstalling and then reinstalling them.

Solution 4 – Reserve the TCP port

If you’ve found other workarounds to fixmodemerror633, feel free to list the troubleshooting steps in the comment section below!

[wl_navigator]

How to fix modem error 633#

How do I fix Error 633: The modem is already in use or not configured properly?#

Solution 1 – Run the built-in troubleshooter#

Solution 2 – Update your modem drivers#

Solution 3 – Uninstall and reinstall your modem drivers#

Solution 4 – Reserve the TCP port#