Firstly I must point out that this isn't a SetupBuilder Issue, but as it
involves Comodo certificates, I thought this might be the best place to
ask for some advice.

I'm actually using Capesoft's Safeupdate to send out an installer that
has been created using my trusty setupbuilder5. I manually code sign the
installer using signtool.

I've found some machines recently that are giving me an error saying
that my certificate is invalid.

I've done a bit of digging, and looked at the certificates that were
installed on those machines, and I expected to find a trusted root
certificate from comodo, and there weren't any. As an experiment I
exported the comodo root certificate from my own PC, and sent that down
to the customer PC, and installed it. If I then re-run my installer I no
longer get an error.

I'm confused. I didn't think I should have to distribute certificates,
as that seems to kind of go against the whole idea.

Am I missing something?

Regards,

Neil.