Hey! Thanks everyone!
I doubt that most folks have turned to Win 10 and that we would be a handful little bunch of Win7 users left in the production world. Many of us, living on deadlines, cannot afford to deal with new problems while there is a stable and reliable system working on W7. If it ain't broke... Not to mention that some aging but still useful hardware may be left behind with no support. AMOF, Tascam itself has not yet published W10 drivers for its DM-4800 (but a beta version is reported to work fine, currently). It is always freaking to feel the obsolescence date approaching and the DM is not so easy to replace. So, my intention was to wait and see. Moreover, I have to deal with Firewire connections... and Win 10 has made a mess on my Offline Video Editing setup (on another machine, you guess) because of the IEEE 1394 thing.
This said, my current system has effectively not received all the updates from MS, this due to some of them failing to install and trying day after day to do so. I had to shut WU automated process off. Despite of this, Platinum worked fine until the last update and a system maintenance. System Mechanic Pro may have corrupt the registry, but it does a backup. That saved me on Sonar X3, while Platinum is out of service.
Another point is that I see the MS Visual C++2015 (32 and 64 bits... ) alongside with all precedent versions in the Control Panel/Programs. Their date stamps are the same as the Sonar PLT update attempts. What does this mean?
Anyway, I will try to load as many MS updates as possible, namely the one that the article Noel gave points to and see what will happen... in a few days. I will rely on X3 for some days, even X2 if needed. The bank can't wait. :P
As for going to Win 10... It is a plunge in the unknown, but the reports we have about IEEE-1394 are scarrying me. I do not want to end with a DM-4800 as a paperweight...