How to fix JavaScript undefined error now

When opening a page containing a ReportViewer control, some users will constantly get a JavaScript undefined error message as you can see from the screenshot here:

We know that JavaScript is needed by many pages to display some contents, especially some animation effect properly. This way, we will be able to enjoy the web pleasantly all the time. But how can you fix a JavaScript undefined error on your own?

The first thing that you should try to do when getting the JavaScript undefined error message is to restart Internet Explorer. Most computer errors are temporary and can be fixed with a little bit of time and a restart of the process for Internet Explorer.

Secondly, just like what I have said in my other post, spyware or viruses are able to severely destroy the Windows registry and stop you from recalling JavaScript correctly as usual. To maintain the security of your computer, you should well protect your PC all the time with a trusted antivirus antispyware program. When the system is able to access all the required files correctly without problem, you will be able to surf the all pages correctly without a JavaScript undefined error message.

Secondly, directly stop the JavaScript undefined error message from showing the alert with the following steps if it appears on only a few pages:

*Run your Internet Explorer
*In the top menu, Click on Tools and then Internet Options
*Click on the Advanced Tab
*Find the tab where says “Disable Script Debugging” and tick the box beside it
*Now, Find where it says “Display a notification about every script error” and uncheck the box beside it.

By the way, you can also clear the browser cache on your computer. We know that a web browser cache is a directory, or a folder having stored copies of the most recently visited websites to optimize the Internet performance. The more cache files on the computer, the slower the computer will be, and the more chances for you to get a JavaScript undefined error message. So do remember to clear the unneeded cache files from your computer regularly.

However, it is highly advised that you can first check the whole computer to get rid of all leftover entries from the uninstallation processes so as to visit all pages correctly without a JavaScript undefined error message. Sometimes, even though you have performed the above steps, some files, entries will still leave over on the computer, especially within the Windows registry. We know that the Windows registry acts like a database of information for all of the hardware and software on your PC. Whenever you install, reconfigure, update or uninstall a program, the registry records all the changes so as to tell the system when & how to perform them correctly. However, an incomplete program uninstall/install, spyware, Trojans and viruses can damage the structure of the registry to make them full of useless, broken, invalid entries. This way, the computer may fail to access them smoothly or quickly. Some leftover entries from the existing registry entries may stop you from reinstalling it again by showing a JavaScript undefined error message. Hence, it is highly recommended that you can first download and run a professional registry cleaning tool to completely scan the whole PC and get rid of all errors inside.

In my opinion, if you want to deal with all PC errors and keep your web browser working at their optimal potential all the time, you need to get a registry cleaner to completely scan the whole PC and repair all errors. This way, no JavaScript undefined error will come to appear on your computer again.