Some versions of Internet Explorer report a "Syntax Error" titled "Errors on this webpage might cause it to work incorrectly" when you login to your cPanel, as seen in the following screenshot:
If you're sure you're accessing the correct page to login, using one of the following login URLs:
https://yourdomain.com/cpanel
https://yourdomain.com:2083
https://serverhostingname.helloworldwebhosting.com:2083
* replace "yourdomain" and/or "serverhostingname" with the correct information.
Then simply click the "close" button and you should have access to your cPanel.
The reasons for Internet Explorer intermittiently reporting "an error" (this isn't an issue with any other web browser) on the login page could be a lot of things. Looking at a list of Internet Explorer Error Messages, if you scroll down to "Errors on Page":
This error message is a catch-all statement meaning there is something on the web page that the browser either hasn't read properly (connectivity problem) or there are missing items in the web page itself. This problem normally affects the graphics on a web page.
This can be a temporary glitch (caused by insufficient bandwidth), and may be quickly resolved, or it can have a more complex and longer term problem. With regard to most cases of this Internet Explorer Error message, it is due to not having given sufficient time to download the page you are requesting.
It is necessary to wait until the bottom left hand corner of the page reads 'done' before selecting any other links on the page to move forward.
