I have found that today my Word dotm template signed with a valid code-signing certificate is suddenly showing a 'Macros have been disabled' warning in Word 2013 and requires clicking 'Enable content' to run. The certificate is from Thawte, shows as 'OK'
and is one of my trusted publishers (plus I have the private key).
This is always true if the dotm file is run from the STARTUP folder at C:\Program Files\Microsoft Office 15\root\office15\STARTUP.
It has only started today and so I think highly likely it is due to the Windows Update KB3199209 for Windows 10 that was installed today. Before today and KB3199209, there was no problem.
I have tried the dotm on two other PCs which both installed Update KB3199209 today and get the same behaviour. I get a 'Macros have been disabled' warning in Word 2013 and have to click 'Enable Content' to run the dotm even though the certificate is valid,
shows as OK and is a trusted publisher.
My main PC is 64-bit Windows 10, the two other PCs I tried were 32-bit Windows 10.
Are other people experiencing problems with signed macros in C:\Program Files\Microsoft Office 15\root\office15\STARTUP on Windows 10 PCs with KB3199209 installed?
Thanks.
PS I don't have access to Word 2016 to check if it's happening with that or just Word 2013.