Hello all.

I'm pretty new to networks and Mikrotik, but so far I'm loving it!

I have a little problem though, I had a working setup with a 4G dongle straight in the MT usb port.
Now reception is pretty bad here so I brought the dongle outside and used a usb extension cable. Thing is, as soon as I put anything between the dongle and the MT, internet will not work.
I tried an active usb cable (10m), a normal extension (3m) and both with a Y-power injector.

So now I have plugged the 10m active usb directly in to a pc, this works very well.
I thought I'd share the internet connection through this pc to the entire lan.
I cannot seem to get this to work either though. The other pc's still have access to my NAS over the lan, and even to the folders on the pc that has the internet. But internet does not get shared.

Just tried to ping - I can ping other pc's from the internet pc but I cannot ping the internet pc from others.

Does anyone know what I can do next?

I could really use a hand here, still haven't figured this out.
At the moment I am using the dongle on one of my pc's to feed the internet to my LAN, however this does not work either.
I can use my internet pc's shared folders across the LAN but its internet is not being shared (tried to bridge the connection and the 'share this pc's internet' option from win 10).

bump :D

I guess the problem with USB dongle, long cable and MT is powering. LTE dongles tend to draw pretty high power which can easily exceeed standardized power capability of USB 2.0 port (500mA at 5V is mere 2.5W), specially so if LTE signal is weak (which is the case in this case) and modem transmits at full power lots of time (usually LTE devices transmit with power up to 200mW, but that's radiated power and power amplifiers have quite some losses. And then there's SoC with its own power requirements). Long cable causes voltage drop and LTE stick may try to compensate that by increasing current draw (making problem even worse). Some USB ports (e.g. on your PC) may provide higher power output which can make setup work.

You might get your USB stick to work if you use powered USB hub at the far end of the 10m USB cable and plug LTE dongle directly in the hub. If that succeeds, you can try similar setup, but with that hub located near MT router.

Thank you for your reply!
I have tried a Y cable, plugged in the extra power usb to a 5V phone adapter. That did not work.
But I will try a powered usb hub next, thanks for the suggestion.