[Bug 1873687] [NEW] could not calculate upgrade while upgrading to 18.04

Public bug reported: While trying to upgrade to Ubuntu 18.04, I get this error message: Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade. This was likely caused by: * Unofficial software packages not provided by Ubuntu Please use the tool 'ppa-pur

[Bug 1873688] [NEW] could not calculate upgrade while upgrading to 18.04

Public bug reported: While trying to upgrade to Ubuntu 18.04, I get this error message: Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade. This was likely caused by: * Unofficial software packages not provided by Ubuntu Please use the tool 'ppa-pur

[Bug 1873689] [NEW] could not calculate upgrade while upgrading to 18.04

Public bug reported: While trying to upgrade to Ubuntu 18.04, I get this error message: Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade. This was likely caused by: * Unofficial software packages not provided by Ubuntu Please use the tool 'ppa-pur