Configure invalid hashing algorithm

Supported on: At least Windows Server 2008 R2 or Windows 7

Registry

HKCU software\policies\microsoft\office\16.0\common\signatures

Options

invalidhashalg enum
  • MD5 -> md5
  • SHA1 -> sha1
  • SHA256 -> sha256
  • SHA384 -> sha384

Description

This policy setting allows you to configure whether Office displays a digital signature as invalid when it contains specific hash algorithms. If you enable this policy setting, you can specify the weakest hash algorithm that Office treats as invalid. If you enable this policy setting, you can specify any of the following algorithms: - MD5 - SHA1 - SHA256 - SHA384 If you don’t configure this policy setting, Office won’t treat digital signatures as invalid because of the hashing algorithm. For example, if you set MD5 as the invalid hashing algorithm Office treats MD5 signatures as invalid.