Allowing the user to revert a version of software to a previous version is an essential part of maintainable software development and deployment. Even if this is an uninstall and a re-install of an older version. In my experience every system is unique and when software is deployed you can never guarantee 100% install success.
A while back I was on holiday. But before I went I tried to update the software on my satnav. The satnav had been nagging me for months to update my maps and I also needed to add the maps for the location I was going to. So I downloaded the map upgrade and because there was not enough internal storage on the satnav I could either keep the maps for the region I was in or I could install the maps for the new region. However I wanted to keep both.
So I went out, got a micro sd card, plugged it into the satnav and re-installed the maps for both regions. As part of the update there were also a couple of software updates outstanding so I installed these as well. It all went well, the satnav asked me to reboot and so all was good.
But after I re-started the satnav, it complained that there were no maps installed.
I plugged the satnav back into the laptop and low and behold the maps had not been installed on the micro sd card, and they had been wiped from the internal storage of the satnav!
I checked the backup location of the maps in the satnav software on the laptop and I could see the maps were there so I thought I was still in the clear.
So I tried the install process again. Still no luck, the maps were still not there. I tried a file copy, that didn’t work either. Over the next three to four days I spent a couple of hours each night trying to get the maps installed. I googled, bing’d (is there such a word?). I contacted the support helpline. Nothing! All I now had was a lump of circuitry which was useful for nothing more than a paper weight!
To be fair, the satnav makers support did get back to me. However it was 2 weeks later and by then I had installed an app on my phone instead which did the job nearly as well and good enough for my needs.
So If you are a developer of software always consider the scenario where an install might break something or go wrong. Because I’m sure you wouldn’t want to fall into the no route back satnav trap!
Have you had problems with software not installing correctly and then not being able to revert to a working version? If so I would love to hear about your experiences so why not leave a comment.