I too am having trouble since latest upgrade, however when it try to downgrade yum fails per below. Any suggestions?
[root@localhost Download]# yum downgrade hplip-common hplip hplip-libs hpijs
Loaded plugins: refresh-packagekit
Setting up Downgrade Process
Only Upgrade available on package: hplip-common-3.10.2-1.fc11.i586
Resolving Dependencies
--> Running transaction check
---> Package hpijs.i586 1:3.9.2-4.fc11 set to be updated
---> Package hpijs.i586 1:3.10.2-1.fc11 set to be erased
---> Package hplip.i586 0:3.9.2-4.fc11 set to be updated
---> Package hplip.i586 0:3.10.2-1.fc11 set to be erased
--> Processing Dependency: hplip = 3.10.2-1.fc11 for package: hplip-gui-3.10.2-1.fc11.i586
---> Package hplip-libs.i586 0:3.9.2-4.fc11 set to be updated
---> Package hplip-libs.i586 0:3.10.2-1.fc11 set to be erased
--> Running transaction check
---> Package hplip-gui.i586 0:3.10.2-1.fc11 set to be erased
--> Finished Dependency Resolution
Dependencies Resolved
================================================== ================================================== ====
Package Arch Version Repository Size
================================================== ================================================== ====
Downgrading:
hplip i586 3.9.2-4.fc11 fedora 6.6 M
hpijs i586 1:3.9.2-4.fc11 fedora 1.6 M
hplip-libs i586 3.9.2-4.fc11 fedora 147 k
Removing for dependencies:
hplip-gui i586 3.10.2-1.fc11 installed 2.6 M
Transaction Summary
================================================== ================================================== ====
Remove 1 Package(s)
Reinstall 0 Package(s)
Downgrade 3 Package(s)
Total size: 8.4 M
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Check Error:
file /etc/hp/hplip.conf from install of hplip-3.9.2-4.fc11.i586 conflicts with file from package hplip-common-3.10.2-1.fc11.i586
file /usr/share/hal/fdi/policy/10osvendor/10-hplip.fdi from install of hplip-3.9.2-4.fc11.i586 conflicts with file from package hplip-common-3.10.2-1.fc11.i586
file /usr/share/hplip/data/models/models.dat from install of hplip-3.9.2-4.fc11.i586 conflicts with file from package hplip-common-3.10.2-1.fc11.i586
Error Summary
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Solved. seems cups keeps the previous driver which of course does not exist any more. Change the driver to 3.10 from 3.9 and all is working again.