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We've bought a Sony Vaio PCG-4121EM supposed to have a built-in 3G modem. It has a SIM-card slot at its bottom. We've inserted a newly-bought SIM-card but nothing happened and the modem is still not visible among the computer devices (neither in Windows device manager nor in "Modems" Control Panel applet). How to turn it on?

I would usually seek to turn a built-in device in the BIOS setup, but there seems to be no BIOS setup on this Vaio - Windows 7 splash screen appears immediately as I turn the computer on.

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That number lines up to a few different versions of the same model. Are you SURE your model has a 3G modem (having the SIM slot doesn't automatically mean it has the modem)? Have you contacted Sony support yet? – Ƭᴇcʜιᴇ007 May 30 '12 at 17:01
Physical lack of the 3G modem inside was my first suspicion. But the girl who was actually buying the laptop says that 3G modem feature was explicitly specified at the shop, she was told she can insert a SIM card and use the Internet... Thanks for the idea of contacting Sony - it seems obvious but it hasn't came into my mind. – Ivan May 30 '12 at 17:10
No worries; people are so used to bad support from everyplace that I'm not surprised you didn't think of it first. :) – Ƭᴇcʜιᴇ007 May 30 '12 at 17:13
I'll combine my comment with some additional info and throw it in an answer. Doesn't mean it's 'right', and maybe other's will come along with a more precise idea, but you can decide that. ;) – Ƭᴇcʜιᴇ007 May 30 '12 at 17:19
There are 3 different versions of the… – Moab May 30 '12 at 17:56
up vote 0 down vote accepted

I know with my UMPC which has a 3G modem in it, it shows in device manager even without a SIM card inserted.

The number provided lines up to a few different versions of the same model. Are you SURE your model has a 3G modem (having the SIM slot doesn't automatically mean it has the modem)?

You may want to contact Sony and confirm with them, and maybe get a little guidance on what to expect from their product.

You may want to also ensure there's no software utility required to enable/disable it.

Mine has such a piece of software, and it (the modem) is OFF by default from the factory until you tell it otherwise, as it can be a significant drain on the battery and (apparently) can potentially mess with WiFi if they're on at the same time.

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I am not sure in anything - the only reason why do I think it is meant to be there is because so was it stated at the shop. I have contacted Sony but they insist on the computer registration before they tell me anything at all, and it makes no sense as we can be willing to return the computer if there is no 3G modem. Regarding a software utility - that's why I actually ask: maybe someone here knows about it. I've actually tried "Vaio Control Center", "OneClick Internet" (both are official Sony tools preinstalled on the actual laptop) and "DC-Unlocker" and none of them can find any modem. – Ivan May 31 '12 at 21:09

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