I understand that there is a site or a webpage that pops up each time that says that you you have a virus. First I would reinstall Firefox for Android or delete the cache. The Firefox cache temporarily stores images, scripts, and other parts of websites while you are browsing. <br> Note: ''This will temporarily log you out of all sites you're logged in to.'' To clear cache and cookies, do the following: #Tap the menu icon located at the top right corner. This is the icon with 3 bars. On older Android devices you'll have to press the hardware menu key and then tap More. #Tap '''Settings'''. #After that, you will be taken to the settings screen. In the settings screen, look under the section '''''Privacy & Security''''' and select '''Clear private data'''. #You will then be taken to a list of what can be cleared. Select the following 2 for deletion: #*Cookies & active logins #*Cache #After those have been selected, tap the '''Clear data''' button to actually clear the cache and cookies. Second, if there was indeed a virus, Anroid is pretty stable, but you can find a security app in the Google playstore as well. The choice of scanner is a matter of opinion so I will leave the choosing up to you. Did this help you with your problems? Please let us know!