It's been really hard to make sketches in SW 2016. Most of the time I click a place on my sketch to create a line no line shows up. After several tries I get a line, but when I click the second endpoint the whole thing disappears.
That's not a lot of information to go on to figure things out.
Can you send some screen shots of just a time when you are able to put one line down and before you click for the second end point see if you can click on the print screen or snipping tool and post the image.
Also, what service pack are you using?
What version of Windows?
What are your computer specifications.
It is most likely a video card issue but hard to tell at this point.
Have you checked to see that your video driver is up to date? - This is a common cause of video problems.
Another thing to do is use the copy settings wizard (from the start menu/ All programs - under the Solidworks folder, and tools:)
use this to save all your settings BEFORE you make any changes.
After you have saved your settings,
Run the Solidworks Rx 2016 program (in the same program selection menu as the Copy settings wizard).
Run the option (shown below at the red arrow) "... bypassing the Tools/Options settings"
Then run SWX again and see if the problem is fixed. If it is, then one of the settings or options you changed caused the problems.
If this did not fix it, Try the option for OpenGL (shown with the blue arrow).
To fix this problem, you need to reset your registry.
If you have a custom user interface save it using "Copy Setting Wizard".
Steps to fix your issue:
Hope this helps,
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