So I haven't updated my SailBusDublin app in a little while because my dev tools were broken. I was getting an error:
Error connecting to "MerSDK" virtual machine: Failed to start virtual machine "MerSDK"
At first I thought I haven't done anything other than update the tools and was a little annoyed at jolla for breaking them but then I came to my senses, people were clearly publishing apps on the store so it was probably an issue on my end.
I figured it was something easily fixable so did a little googling and couldn't find anything.This is not as weird as you might think given the size of the developer community so I decided I'd leave it a little while and someone else would run into the problem and fix it (the it's a side project and I'm being lazy approach) but alas while some people ran into it, no one seemed to fix it. So I decided to put the effort in and debug the issue.
It's fairly clear from that error that it's an issue with the VM so I opened virtual box rather than bother with QtCreator again and tried to start the VM and got an error about intel's VT-x which was weird because I didn't remember making any changes to my laptop in regards to virtualization. Anyway found some redhat docs on the issue:
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Administration_Guide/sect-Virtualization-Troubleshooting-Enabling_Intel_VT_and_AMD_V_virtualization_hardware_extensions_in_BIOS.html
and went into the BIOS and turned it back on and voila the "MerSDK" VM started and I was back up and running.
I think I turned it off at some point because of a security issue with VT-x but the only issue I can find of the subject can't be exploited on my laptop because it's 64-bit running a 64-bit host. That said if your running a 32-bit host be careful of the VM's you use if you re-enable VT-x.