When JavaScript is disabled on a Windows browser, users may experience issues such as websites not loading properly, unresponsive buttons, videos not playing, and online forms or payment processes failing. Enabling JavaScript is generally safe and is necessary for most reputable websites to function correctly. The process to enable JavaScript is straightforward and does not require advanced technical knowledge. Many browsers, like Firefox, have JavaScript enabled by default, although some users may disable it for privacy or security reasons. If websites malfunction after enabling JavaScript, troubleshooting steps include clearing the browser cache, disabling extensions, restarting the computer, updating the browser, or checking antivirus restrictions. Users on work devices may need to consult their IT administrator for assistance.