"Cannot open the file because the file format or extension is invalid" opening Office files

   UPDATE:  We have identified the malware as a new family of ransomware Infection: Trojan:Win32/Bumat!rts AVSubmit Detectable with AM definitions version:  1.157.1559.0 or laterhttp://www.microsoft.com/security/portal/threat/encyclopedia/entry.aspx?Name=Trojan%3aWin32%2fBumat%21rts&ThreatID=-2147341227   Infection: Trojan:Win32/Crilock.A. Detectable with AM definitions version:  1.157.1542.0 or laterhttp://www.microsoft.com/security/portal/threat/encyclopedia/Entry.aspx?Name=Trojan%3aWin32%2fCrilock.A   Definition Information:     Latest public Endpoint AM defs:  1.157.1542.0 (Expect several hours later for 1.157.1559.0 or higher)      http://www.microsoft.com/security/portal/definitions/whatsnew.aspx     Latest Prerelease…

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