Q: I get an error when I try to upgrade to the next version of a program.

A: Starting with RTG Bills and RTG Timer V2.20, you must obtain a license key from RTG and download the installation file in order to upgrade.  See Upgrading RTG Bills.

Updates (as opposed to upgrades) do not change the RTG Bills version number.  They may add optional features or they may fix problems in the current version.