Dec 7, 2015
Microsoft will NEVER call you, text you, or place any popup on your screen indicating that your computer or mobile device has issues and that you should call them immediately to get it fixed.
Generally these tactics are used by scammers based in India.
The real Microsoft phone number is 1-800-426-9400. If you did not initiate a call with them on the 800 number first, they should have no reason to call you.
If you feel sketchy about the call or text you received, try giving Microsoft a call on the 1-800-426-9400 number for more information about scams.
Hope this information helps!
UPDATE: I just did a quick database search on 425-409-2621 and it is in no way associated with Microsoft. It is likely a computer number used by scammers as I mentioned above.