Seems that Windows Vista is not supported for earlier versions of DWG Trueview either. See: System Requirements for DWG TrueView 2013-2016. As such, I suggest you upgrade your operating system. Lynn Zhang 2013 64-Bit doesn't list Windows Vista 64 bit but I was able to install 2013 64-Bit and it runs ok under Windows Vista 64 Bit. I have not tried to install 2014 or 2015. You're correct Windows Vista is a much older OS, beginnings date back to the advent of XP. However it's still being supported a while longer by Microsoft for security and other types of updates. I've been upgrading my PC's and OS for more than 35 years. My next upgrade will include a new PC. I'm not certain of the actual cost to upgrade my current PC which sold new for around $1500.00, most likey a similar or higher cost to upgrade. I have older laptops that retailed for around ~$3500.00 when new to upgrade to new cost is around $4,000.00+ for each laptop. It's benefical when upgrading an OS that your hardware architecture is more recent. Vista run ok with my current hardware.
