I tried reproducing it in both 6.10.10 and 7.17.2 but could not. Are you saying you experience the issue in different applications than the Modeler as well?
It might indeed have to do with a recent update on your machine. My machine had the latest update on August 27 (KB4100347: Intel microcode updates).
If I look at where it goes wrong in the Modeler source code, it is calling GetCaretBlinkTime deep inside WIndows (user32.dll) to get the speed of the blinking cursor and then it tries to initialize a timer with that interval. Apparently, on you machine the answer of GetCaretBlinkTime is -1 which is not a valid interval.
Did you install a utility that does something to your cursor?
Fixed - by changing the keyboard properties. Thanks Arjan - it made looking for the issue much easier!
Place the Cursur blinking rate one higher then none.
The issue with the Desktop Modeler not being able to handle cursor blink rate 'None' will be fixed in Mendix 7.19.0.