@mitu Yeah -- there's no error message readily available when the runcommand dialog isn't shown. I should probably just do a clean install since that is the recommended route, likely something didn't upgrade correctly at you say.

@mitu thanks for reply. The original fresh install was years ago. From memory I followed the instructions from an ETAPRIME YouTube video

@GreenHawk84 I totally get this. It took months to get my build perfect to the point I was only adding around 1 rom at a time so I could scrape and detail it perfectly. Now we have a huge upgrade it makes my palms sweaty so I don't mess anything up lol.

@jorgenjl Get a Linux live distro (Ubuntu/Fedora/etc.), write it on an USb stick/CD and boot it up on your PC. You'll be able to read the SD card's contents to copy over your configs/roms, then write the latest RetroPie image on your SD card and transfer over your data.

@wizardling Shucks, I'm blushing here. But seriously no problem at all, just browsing the forum and saw your post and noticed you were using apt and was aware it sometimes can cause issues like this.
The "problem" is that Linux will do exactly what you tell it to do and if you aren't fully versed in exactly how things work it can cause problems. I honestly couldn't tell you why it works, other than it handles installation of packages and dependencies differently.