Dear all

I'm using an Archer MR600 with an O2 data SIM on a PC running Windows 7 Pro. This model wasn't shown in the pre-selected list, so I had to use the AP300 from the dropdown list just to be able to post this.

We are in a rural area where BT broadband over copper is providing a blistering 0.36mb download. I'm using the above and I'm getting really good upload and download speeds from the SIM which is an unlimited data SIM.

The problem is I can't seem to achieve a secure FTP connection to external webservers using FileZilla and FTP over TLS. I can get plain insecure FTP, but I'm not going to use this.

O2 network team are looking into it (not holding my breath), but they assure me there are no restrictions on the network using the SIM.

The webhosts blame the O2 4G network and the internet connection achieved via the network.

A friend has managed to FTP over TLS to the same account I'm trying to connect to, tethering his phone and using his Sky SIM - which uses the O2 network. We are using identical settings in FileZilla. He is saying it may be something to do with the router or router settings.

I have tried turning off all antivirus and firewalls temporarily, but I still can get a connection to the webserver.

I wonder if anybody else was having these problems and have have found a solution? I can connect without a problem using my BT broadband, but the uploa speed is even slower than the download.

Many thanks