Firefox cannot connect to Yahoo!

Firefox cannot connect to Yahoo!

You said that you cannot view and browse Yahoo! website in your Mozilla Firefox . There are possible reasons about that issue. One of which is that you mistakenly do a config change to your proxy settings, a mistake that a person does unintentionally. You will noticed that you cannot view a single site or much worst, you cannot even browse the internet in any manner. Another reason is that your Mozilla Firefox does have a corrupted parts or portions wherein you cannot use your Firefox properly. This is probably caused by some viruses gotten through USB drives, by downloading infected files through the internet. Another possible reason is that your firewall does not allow your browser for incoming or for outgoing, or even both connection. This is caused by mis-configurations made in your exceptions in your firewall or even unusual mis-configuration caused by viruses.

One of the possible solutions to this problem is running the Mozilla Firefox in safe mode. In this mode, installed plug-ins by user will not be used and default set-up of the Mozilla Firefox are the ones you can use in this mode. You can try to browse to yahoo.com website. If this solution does not make any sense and does not work, you can try the second solution and that is by repairing the Mozilla Firefox by means of reinstalling Mozilla Firefox via repair method. In this case, you will run the application of installer file of the Mozilla Firefox. Select option. 

Repair, then click next button. If you want to retain your existing settings, you can do so but I do suggest to repair and just set your settings to default and do the reconfiguration later. After the installation, if necessary configurations including the network settings, download locations, etc., are required. You must do it after the repair process. If in this case, the second option did not work, well, you can do the next one and that is the uninstalling of Mozilla Firefox, make a restart, and install the latest version. You must do an uninstall using the add- remove programs of Windows or by using the option uninstall Mozilla Firefox in the start menu or even using the installation file of Mozilla Firefox by choosing, remove options. After uninstall process, you are required to reboot your PC to remove Firefox files. Then, you can run the set-up application of Mozilla Firefox until it is finished.

If reinstalling Firefox does not solve your problem, probably it is your operating system that has the problem. You can try to use chkdsk utility in the command prompt and just do a restart and let the windows run a chkdsk. Making a chkdsk does the returning of mis-located files to its proper places. If still this is not the solution to your problem, then it is about time to do a updated full scan of your antivirus installed in your computer. Whatever your antivirus is, you are required to do a full scan and try to delete all the possible viruses in your PC. If still it does nothing, then I would suggest to reformat your PC because your system does not work properly.