Follow this tutorial if you would like to update your iPhone 4 firmware without upgrading your baseband by using TinyUmbrella! It is important that you read the TinyUmbrella readme file before you do anything else. The readme file is located here. Remember this tutorial is only for Window users a Mac version of this tutorial will be available soon.
Note: This tutorial only works with iPhone 4.
Download Tiny Umbrella for Windows
2. Right click on the downloaded TinyUmbrella.exe file (umbrella-4.1.6.exe) and select Run as Administrator the the popup menu.
3. Alot of you might have Windows security enabled, if this alert comes up make sure both boxes are checked and click on Allow access.
4. Please make sure your device is connected so that TinyUmbrella can detect your device and the firmware.
Now click on Start TSS sever and ensure that you receive no errors.
Once The TSS Server is “running” successfully, umbrella will kill iTunes. Leave TinyUmbrella Open.
If you receive an error saying DO NOT CONTINUE. Then your restore will not work until the TSS server can not be started.
6. Now open iTunes and hold Shift and then click on Restore.
7. Navigate to the location and select the iPhone 4.1 firmware file you have just downloaded at the beginning of this tutorial from our download listings.
Click Restore to restore your iPhone
8. iTunes will give you an error (1004). And this what we wanted as this explains that our baseband has not been updated.
9. Now go back to Tiny Umbrella and click on “Kick Device Out of Recovery” as shown in the screenshot. If you have some issues by following this step then close TinyUmbrella and re-open it and do it again.