Hi, Im also trying to upgrade and everyone keeps saying run_upgrade.php but that means nothing to me! I am a total novice and after searching for an answer on forums im still trying to fatham how to 'run' it? Please help!
To 'run' _upgrade.php, you need to bring that page up in your browser and follow the instructions on the page.
Are you upgrading to Beta 3.0 (the download package from the main website page)? If so, then you need to navigate to http://www.yourdomain.tld/plogger-foldername/_upgrade.php in your web browser.