Hi there and welcome
There is a global outage of skype today that is effecting the majority of users.
this is not related to your account or computer and is an issue with the Skype servers themselves that Microsoft is working through as we speak.
there is currently no ETA on the resolution of this and you will have to try hourly to use Skype. Once the outage has been resolve it will then function for you without you needing to do anything special on you computer.
If you would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service by clicking one of the stars at the top of the screen then submit, that would be greatly appreciated.