For Email users who subscribe to a Yahoo service, be it Yahoo Mail, Messenger, groups, news or any other stories, may at some period run into the runtime error 999.
This error happens when you try to open any of the services and you are welcomed with the error message together with a statement that the service cannot be reached at the moment and please try again later. Luckily, there are a few ways to try and fix it.
Instruction for how to fix Yahoo error code 999
1 Start your Internet browser and clear the cookies and cache files. This can be achieved by clicking on Tools and then on "Delete personal data" in Firefox. Click on Tools and Temporary Internet files in Internet Explorer and Safari, click on Safari, preferred Choices and then Internet cookies.
2 Later Turn off the proxy server if you are connected to one.
A proxy server is a system that goes among the clients and the user. If you are not part of a proxy server, jump this step.
3 Download another browser. This resolves the problem, particularly if the other two stages have not yet reviewed. Firefox, Internet Explorer and Safari can be downloaded through the Resources section.
4 Start the new browser and try to reconnect to the Yahoo desired. It should charge evenly.
Go through these 4 steps and fix your Yahoo error code 999 but in case if you are unable to solve this issue by following the above steps then contact Yahoo technical support department to solve this issue.
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