Cydia didn't want to open (Ipod Touch 4g FW 4.2.1)

[Evidence]

Hey guys !
I just bought me an Ipod Touch 4g after christmas and yesterday I tryed to Jailbreak It.
I took Redsnow 0.9.7 Beta 3 (And 0.9.6 beta 2-3-4) and the same probleme is always happening.
Everything seems to goes great...my ipod is jailbreaked but when it reboot and I goes to open cydia...oops.
The Icon is blank and when I click on it, a windows is opening but suddently it close. Is someone can help me ?

Im on FirmWare 4.2.1 with Ipod 4g (MC models like every ipod 4g I think ?)

Thanks
Hopefully someone will know what to do !

[Simon]

Do you have 4.2b3 SHSH?

[Evidence]

No I don'T
What I have to do if I download it ?

[Simon]

0.9.7 wont work without 4.2b3 SHSH. 0.9.6b6 should work, you will need to run redsnow again and choose boot tethered though for cydia to open.

[Evidence]

But I can't Jailbreak Normaly (Untethered Mode) with Ipod 4g ?
My friend just tryed and his Ipod seems to be jailbreak (with cydia available) in untethered mode.

[Simon]

Right now the only way to do it is if you have 4.2b3 SHSH and a copy of the 4.2b3 firmware.

[Evidence]

Can you tell me how/where I can get 4.2b3 SHSH ?
And 4.2b3 firmware..?
I only have the Copy of 4.2.1 and 4.1 FW

[Simon]

You can download the latest tiny umbrella to find out if you have 4.2b3 SHSH. The Firmware Umbrella - TinyUmbrella

[mortopher]

0.9.7 works for the tethered jailbreak as well. No need to download 0.9.6. Just put your IPT in dfu mode and run the "just boot tethered" option.

[Evidence]

Yeah but I want to run it in untethered mode !
When I did it cydia didn't open.