upgrade from 3.1.2 to 4.2.1 fromware

[zukin2956]

have a 3gs with 3.1.2 to the latest firmware which can be jailbroken & unlocked.
I downloaded 4.2.1 ispw file, tried doing the upgrade with itunes and i get the
message that says it is not compatible.
any ideas?

thanks in advance.

 

[redhotline]

sure?

do you sure you downloaded firmware for your model??

 

[Applejuiced]

You need shsh blobs for 4.2.1
Without them you can only update to the latest 4.3
Open up cydia and look at the top of the page to see what shsh: you have listed there.

 

[zukin2956]

You need shsh blobs for 4.2.1
Without them you can only update to the latest 4.3
Open up cydia and look at the top of the page to see what shsh: you have listed there.

where abouts on cydia do I get this info?

 

[Applejuiced]

where abouts on cydia do I get this info?

When you open cydia look at the top of the page. It should list the versions it has blobs saved for.