During the latest Windows 10 Creators Update (11 April 2017), Microsoft has moved a bunch of files in a windows.old folder. For some reason, the OpenCl.dll was moved to this folder and wasn’t replaced.
Mosketch as many other graphical applications cannot run without the proper OpenCl.dll. We cannot provide a fix for this as every user will have a different graphic card and a different OpenCl.dll version, but you can easily fix the issue by re-installing the latest drivers of your graphic card. Ignore the fact that it tells you that your drivers are up to date and re-install them anyway.
That should solve your issue. Hope this article was helpful.