How can I install a game on the Motorola RAZR2

October 21, 2008 1:06 PM

Did you ever install an application on your RAZR2 V8? If you did (or know how to), could you please tell me how?

I have an unlocked Motorola RAZR2 V8, in the UK. I've tried several programmes to install a .jar game on the phone, but nothing has so far worked.

Getting the game onto the phone isn't the problem. Installing it is. I get a warning that the file in question (I've tried about 20 different .jar games/apps) isn't a signed application. I click continue, and get a message saying "installation failed".

I've spent hours Googling, and trying various different methods, but they all seem to assume that getting the game to the phone is the problem.

What am I doing wrong?

posted by Solomon to Grab Bag (4 answers total)

Unfortunately, it's entirely possible for a carrier to lock down a phone such that it will not install any unsigned applications--that is, applications the carrier itself hasn't vetted and signed. You can't fake the signature, as it's cryptographically tied to the data of the application itself as well as the carrier's secret keys.

More unfortunately, there's not much you can actually do about it. You *could* try getting a new certificate store, one including a self-signed "root" certificate, and installing it on the phone... but, you need very low-level access to the phone to achieve this. If you could pull this off, you could then sign your applications against the false root certificate, and get them on the phone. But, IIRC, the certificate store itself is protected on Motorola phones.

(Please note that this has nothing at all to do with the carrier lock on the handset, which is the only thing removed when you "unlock" a phone. Now, if this is a phone you bought directly from Motorola, with absolutely no carrier having ever touched it, this may be an actual technical problem with a feasible solution, and not just a carrier setting.)
posted by Netzapper at 1:57 PM on October 21, 2008

It's been a very long time, but I seem to remember that you needed both a .jar file and a .jad file. Do you have both?
posted by kidbritish at 4:40 PM on October 21, 2008

Oh, well, there is that.

You should be downloading a .jad file that refers to a .jar file. You can't usually do it with just a .jar.
posted by Netzapper at 4:59 PM on October 21, 2008

Yeah, I have both the jar and jad. I'm using the files from getjar.com (a fantastic website for Java games), but even having them both on at once makes no difference. :(

Using P2kman, I can get access to what appears to be a Linux view of the phone, with various folders and files. I have no idea what to do with it once I have it, though, lol.
posted by Solomon at 12:50 AM on October 22, 2008