Calls from alleged Microsoft employees are frauds

Scammers pretend to be Microsoft technical support center agents who contact you with PC alerts or phone calls, and claim your computer is infected with viruses. This criminal scam is known as "Tech Support Scam",  and unfortunately it is currently experiencing an upswing.
Our PC CADDIE staff are also faced with these calls and would like to pass this warning on to golf clubs and golf courses. THE KEY FACTS

• Beware of fake PC alarms or calls from alleged Microsoft employees trying to convince you that your computer is infected by viruses.
• Microsoft says its employee don't make any unsolicited phone calls to repair damaged equipment. Even official support requests are made almost exclusively by e-mail.
• If you are called by an alleged Microsoft employee, end the call immediately.
• If you have already spoken to one of these alleged Microsoft employees, disconnect your PC from the network and change your passwords.

Source Consumer Center:
https://www.verbraucherzentrale.de/aktuelle-meldungen/digitale-welt/warnung-abzocke-durch-angebliche-microsoftmitarbeiter-24641 (in  German, last accessed on 24.08.2018)

Source Microsoft News:
https://news.microsoft.com/de-de/microsoft-anrufe-scam/ (in  German, last accessed on 24.08.2018) Microsoft asks you to report every case, in order to be able to act against this frauds. The link to the corresponding form can be found here: http://support.microsoft.com/reportascam.