Ever since iPhone Dev team released Redsn0w 0.9.10b2, which included a fix for the launchctl issue, a number of readers have reported that many jailbreak apps stopped running after re-running Redsn0w.
iPhone Dev team has just released a new version of Redns0w 0.9.10b3, which fixes the problem. They have provided the following information on their blog:
The b3 version of redsn0w fixes a problem where re-running redsn0w over an existing jailbreak would cause MobileSubstrate-based apps to stop running until MS was installed again. Now you can re-run the redsn0w jailbreak step without worrying about that (but still remember to de-select the “Install Cydia” option if it’s already installed).
They also have the following tip for users who may have hit "no identifying data was found" while using Redsn0w:
TIP: If auto-detection fails and redsn0w tells you no identifying data was found, you can always pre-select the appropriate 5.0.1 IPSW using “Extras->Select IPSW”.