Thanks for the replies. This will probably be a long one. Hope there's enough space on the internet 
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Do you have any peripherals attached to your machine? (Wacom tablets, 3D mouse, USB Bat Signals, anything?)
I have a lead that came with my monitor. It goes from the monitor into USB. This makes it possible to use the USB ports on the monitor.
I either have the mouse or keyboard plugged in the monitor (because its lead was too short). The other device (mouse or keyboard) I have plugged into the system.
Right, at this point I should say that I do have a system that's caused me some headaches. Last year the mouse and/or keyboard would stop working at random intervals. I had to swap the ports they were using. It got to a point where even swapping didn't help and only a restart would. This issue seemed to sort itself out and I haven't had the problem for ages.
Also, another annoyance. Something new I'm getting Win10. This seems to happen between 2 & 3:30pm....... My mouse, keyboard and then monitors stop working. Monitors go into standby. Sound works for a while but then goes weird. I think the only way I've been able to fix this is to force a restart. I don't think it restarts by itself. As it happens in the afternoon, I don't have the time to see if it self restarts. I don't get a BSoD.
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The system has 1x GFX card. It's a GeForce GTX 770
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I can't begin to understand what I'm seeing in the event viewer. Here it is, if you can take a look.
https://dl.dropboxusercontent.com/u/7680428/ST_eventViewer.zip
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but you've already tested RAM so we can discount that
Well, I have Speccy installed and all of the RAM is the same type and not giving warnings.
Lastly, if you are running a dongle of sorts (like Wibu for Vray) it may be that the drivers for it are not installed correctly. Do you use a dongle for any reason?
My boss has the dongle for Vray in his system. I don't have one.
Updating Max
I had just finished updated them one by one when I saw your message. I'm now up to date. I hadn't installed any updates after installing Win10
AppData
I've kept the 2017_x64bit folder that Max created when I first ran it (after installing Win10) but renamed it. Max created a new folder in there so I'm seeing how that one goes.
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I'll give Silentium a try, thanks for the tip. Yeah, I don't think we're using ForestPack the best way in the office. Thanks for the other Max info at the end of your last post.
Many thanks again.
Sean