sounds like you have a virus... does it have an amount below it that shows "possible network damage" if you dont call and fix it? whatever you do, dont call that number... they will coax you into giving them remote access and then its all over...

you have a few things you can do depending on your AV/MW protection status...

first thing i would go to http://www.malwarebytes.org/ and either get the free version or the wise choice would be pay the 25 bucks and get the premium version... you can only run scans with the free version, the premium has real time protection that is incredible... i have had zero problems in the last 6 or 7 years using it...

run the scans, do the flash scan then full comp scan, then scan it with your normal AV (if you are using windows defender, i suggest getting another AV), if you dont have one, AVG works great and is free, Avast is another one that is free... i personally dont care for any Norton or McAfee products, Kaspersky is good but spendy...

http://www.avg.com/us-en/homepage

my neighbor recently had to deal with this, and he stupidly called the number and was told that it was 400+ dollars for the man over the phone to fix it, then when he said he wasnt paying, the icons on his desktop started disappearing and things started getting deleted... i came in right when it was almost too late and saved his ass luckily...

so my advice is to do what i said above, and stay off the phone...