Hello,
RM does not start, process reefmaster.exe terminates, until this moment everything worked fine.
I tried different versions - 1.8, 2.0.
Can you help me?

Windows 7 prof, SP1

Have you changed anything in your OS recently? That's an odd error that I haven't seen before. When does the crash happen - do you see RM start up at all, or does it fail before it becomes visible?

Only this Windows updates, I tried to delete them, but it did not help.
Crash happen before RM becomes visible.

It might be worth installing .NET v4.1 to see if that makes any difference. Are any of your other installed applications having issues?

RM breaks after upgrade .NET Framework to 4.7.

OK, thanks. We've looked into this a little and this is a problem that a lot of people are having, with many different applications, on W7 and W8 machines after updating to .NET 4.7. It is an issue with .NET and there is nothing we can do at our end to fix it, other than to hope that Microsoft release an update as soon as possible. In the meantime, you may need to remove the .NET 4.7 update to continue using ReefMaster.