WebInspect smart update error
Take a look at the following forum/discussion post regarding this issue: https://community.microfocus.com/t5/Fortify-User-Discussions/WI-and-WIE-Smartupdate-error-Invalid-signature-on-file/td-p/1687709
After successfully installing once in 19.1.0 you should no longer experience this issue. You will continue receiving this error as there are older executables in your environment that need to be replaced as mentioned in the link above.
I had a similar issue with 18.20 -> 19.10.
In the end I had to pull down a brand new version, uninstall old and install new.
Maybe smart update needs to get a little smarter?
Have not tried smart update since we moved to 19.10
Also, make sure you replace all .exe's with the one contained in the link above. If you continue to have problems please submit a support ticket for further assistant.