The problem: When I connect JioFi 3 via USB tethering to my Windows 10 OS desktop computer it takes some time for the browser to connect to Internet sites (a lag issue). After some lag it starts working, and works well for some time. Later it (Internet connection through JioFi 3) sometimes suddenly freezes or slows down terribly (hundreds of Kbps range speed). Chrome browser tends to get stuck/frozen then. At times, but not at all such freeze problem occasions, I even get a no Internet connection message on the browser! After some minutes, the Internet connection recovers on its own and the speed picks up, getting into Mbps range.
Just the speed drop could be attributed to poor location of JioFi 3 router from a signal strength point of view. But the no Internet connection message is a strong indicator of something wrong somewhere.
I browsed for solutions to this problem having JioFi router as part of Google search term. But I did not get suitable results initially as the Jio related result links (mostly from users and not Jio company) did not report such problems. But I think I saw some Windows 10 related links about USB tethering problems (Windows 10 was also part of some of my Google search terms during this browsing).
So then I thought maybe JioFi 3 router is facing a generic problem that 4G routers face with Windows 10 and USB tethering. So I used Google search term: NDIS usb Windows 10 problems
That led me to this link, “[FIX] USB Tethering lags/freezes on windows 8.1”, https://forum.xda-developers.com/android/general/fix-usb-tethering-lags-freezes-windows-t3039183. The solution, it says, is: “Update your NDIS 5 Driver to NDIS 6.x.” and gives the procedure to do so.
It also has this Microsoft link: “Slow startup of Modern Apps when RNDIS devices are connected”, https://support.microsoft.com/en-us/help/2923775/slow-startup-of-modern-apps-when-rndis-devices-are-connected. The problem listed is slightly different from but related to the problem I am facing. But the common issue is the RNDIS device. It says about the cause of the problem, “This issue may occur if the USB device is mapped to a incorrect RNDIS 5 based driver. If the underlying network device uses Remote NDIS (RNDIS) 5 drivers, you may experience slowness in loading the Modern Apps.” To identify whether the network device is using RNDIS 5 drivers, it says that Driver details for it will show files named “usb8023x.sys and rndismpx.sys”!
These are the files shown for driver details of the Android device that gets shown under “Devices and Printers” when the JioFi 3 device is tethered via USB to my Windows 10 desktop comp! So that seems to be it. The incorrect driver is being used by Windows 10 for the USB tethered JioFi 3 router device!
The Workaround suggested by the Microsoft link above is: “Upgrade the drivers to use RNDIS 6.x driver. Contact your devices Hardware Vendor on steps to receive the files/steps required to update the driver so it uses RNDIS 6.x driver.”
But I don’t think JioFi 3 support is that sophisticated to provide (updated) driver files or any driver files for Windows 10 (or other Windows OS)!
However, the earlier forum.xda-developers.com article suggests an easier solution under its option 1 using manual driver update. But it does not have the specifics. Here’s a youtube video which shows how to do it: “FIX – USB Tethering on Windows 10”, https://www.youtube.com/watch?v=tyBS3rVTxxU, 2 min 7 secs. I had come across this youtube video earlier in my browsing but I was not sure whether what it suggested was safe to do. Now I am more confident about it given that Microsoft itself states that the drivers have to be upgraded to RNDIS 6.x. According to this youtube video, if after changing the driver as demonstrated by it, the driver file names are rndismp6.sys and usb80236.sys, the driver would have been updated to RNDIS version 6.
One issue in the above manual procedure is overriding a warning from Windows about installing the new driver (USB RNDIS6) possibly making the system unstable. I think I need to first have a proper system backup to fall back on, if the new driver installation trips up something. So I may explore using this solution only after a few days perhaps.
Overall, I think the above mentioned descriptions fit my JioFi 3 USB tethering to Windows 10 flaky connection problem, and so their suggested solution may resolve my problem.