When i started Solidworks it stops poping message with js error. I hade option Yes/No but eather way i pops it again and i wasn't able go forwar. Only solution was to us 3 magic keys and kill process. Picture 1 shows error:
Error: 'getVertical' is undefined
So to fix it i did this:
1 Go to this path shown i your message (may be diferent depend your installation) fing this file. Hit rename and ad on and extension for file .js. Even if you see your extension add another one. In my case windows settings for folder was checked to "hide known extension" so after that i saw file like it schould be but when i unchecket folder setiing to show extention i saw double extention like taskPaneFuncs.js.js.
2 kill solidworks process
3 start Solidworks again. In my case durring start it shows difrent error with path to C:\Program Files\SolidWorks Corp\SolidWorks\data\taskpane\solidworks resources.html
but when i changed it same way for double html extention Solidworks start ok.
I can't realy explain way it is that way but at least you can fix problem that way. Deleting those files and do repair doesn't fix it. I don't think is Solidworks somehow windows loose ability to recognize those files. I hope it can help to some people, if so please respont to it and we will all know this.