[Solution] Fix Installer v3.1 "Package download failed " & permissions errors
UPDATE: THIS METHOD DOESN'T MAKE INSTALLER 3.X WORKING ON 2.0 FIRMWARE, YOU MUST WAIT FOR THE 4.0 INSTALLER RELEASE
I found a pretty simple but really efficient way to solve Installer 3.1 issues.
NOOB PROOF METHOD (OS X ONLY)
1- Backup/rename your Installer sources folder (/var/mobile/Library/Installer) with SSH, Term-VT100 or Mobile Finder.
If you don't want/care to backup, you'll have to add your sources again and reinstall your apps because the Installed apps list of Installer will be empty and you won't be able to see updated apps.
2- Download the iLiberty+ 1.51 for OS X (previous versions are not compatible with the new payload format).
3- Download the Installer3FIX.lby and save it on your desktop.
4- Open iLiberty and check the "Select a custom payload manually" option.
5- Click Browse and load the Installer3FIX.lby.
6- Click Free my iPhone/iPod Touch !
7- Update you Installer to 3.11 and restore your Installer sources folder.
8- Enjoy your error-free Installer.app :)
- SSH Client: Putty for Windows or Terminal for OS X.
(You can also use TermVT-100 if it is already installed in your phone.
- Your Firmware must be 1.1.3 or 1.1.4.
- You must have or need to install BSD Subsystem.
Restart your phone and from a computer, use SSH to connect to your phone and type this:
Quit SSH and start Installer from its icon on Springboard.
rm -R /var/mobile/Library/Caches/Installer
rm -R /var/mobile/Library/Installer/Temp
chmod -R 755 /Applications/Installer.app
chown -R root:wheel /Applications/Installer.app
chmod 4755 /Applications/Installer.app/Installer
The Permissions and "Package download failed" errors are gone. :)
If after doing this method you still have the "Package download failed" error while installing apps (but not with all of them), they are in fact caused by down repositories, so you might try again later