I've started getting an error on Ubuntu when trying to upgrade packages: "Not all updates can be installed Run a partial upgrade, to install as many upgrades as possible"
When I run a partial upgrade, I get this: "Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade: The package 'postgresql-9.1-postgis' is marked for removal but it is in the removal blacklist. This can be caused by: * Upgrading to a pre-release version of Ubuntu * Running the current pre-release version of Ubuntu * Unofficial software packages not provided by Ubuntu
This is most likely a transient problem, please try again later."
I have PostGres 9.1.9 and PostGIS 1.5.3.
Sounds similar to this problem: https://gis.stackexchange.com/questions/67143/postgresql-9-1-postgis-2-0-ubuntu-12-04-installation-problem