I am between ISPs and need to keep my Three SIM open while my new Sim sits in my Motorola phone. The only phones I have on hand are old candybar phones: a Siemens 1600 and a Doro 410gsm. The Three SIM just returns 'sim error' when inserted into the otherwise functional Doro.

Is this straight incompatibility between the card and old (2010) hardware? Are there limits to what device Three cards will work on? A problem with frequencies or suchlike?

Is there a better chance of its functioning with a scabby smartphone bought for a while from the pawnbroker?

Three will not work on 2G only phones which I'm guessing is your problem. As Three only offer 3G and 4G services the phone must be capable of 3G at the minimum.


To save the pendants having to say it, In few very few places there is a 2G roaming agreement in place but as that probably serves about 0.1% of the UK it likely won't be applicable

The phone has to be 3G capable

No you need a old phone that dose the 2100 band best bet would be to go on the bay ad find a beat up Android phone or a old skype phone

Unless you have a good deal/ old tariffs then id suggest you look elsewhere there masts are very congested and dont seem to want to fix or resolve there issues

Im now with bt mobile far better network as it runs on EE

Thank you all for that reassurance that my backup phone are too old. For Three anyway.

Well it's off to eBay, Gumtree and Cash Generators for a banger then.