Technical Blog Post
Is MS Office 2016 supported with Maximo?
We have had some customers ask if MS Office 2016 supported with Maximo 7.5.x and 7.6.x?
Short answer, MS Office 2016 is currently not supported as it has not been fully tested with Maximo.
However, if you really still want to use MS Office 2016, you will notice some of the functions in Maximo such as the download list will not work nicely and not allow you to open it like previously.
This is because with MS office 2016, a feature called Extension Hardening is enabled by default. It seems the extension hardening was introduced back in MS Office 2007.
By Default, a user can decide to open the file when the warning is displayed, depending on how group policy is enforced. Which is the behaviour you mentioned was occurring in your MS Office 2013.
As a workaround, you can disable the warning by making a registry change as per MS suggestion below.
The key is HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\OFFICE\16.0\EXCEL\SECURITY
If you set DWORD called ExtensionHardening with the default value (0) this enables Maximo to pass the file to excel without any issue.