Looks like you need to reset browser’s proxy settings.
Run Internet Explorer and open the tools menu (icon like a gear). Select Internet Options. Open Connection tab and click Lan settings button. Next, uncheck Use a proxy. Close settings and restart Internet Explorer.
If you’re seeing unwanted pop-ups or ads in your web-browser, you might have an adware installed on your computer. Use the following guide to stop pop-up ads and remove malicious software. Or ask for help here.