Another FSCIMC hung in a start pending state issue.
Before this was tied to execution policy being set to restricted or locally signed
This time certificates are to blame.
If for some reason your Microsoft root authority certificate expires you can expect to see FSCIMC and Edge transport fail to start with the execution policy at the default setting.
We require at least remote signed but if there is an issue with contacting the CA and you have an invalid or expired certificate you will have to lower your exchange power shell script permissions to unrestricted.
This will allow you to start up but the real fix would be to fix your certificates as other issues will occur with updates not able to verify the digital signatures.
This issue occurs because there is a popup warning of an invalid certificate. Since we are running as system we never see that popup and sit and wait for something to happen.
If you remove our produce you will then see a pop-up generated by edge transport with the same information about an invalid certificate.