To change the Bastion certificate you need to edit your bastion.xml file located at:
...
store:/LocalMachine/My/#667B3CC8ADF2B13BB9F4BF258F3232C337EE3389
For the store name you can use:
- LocalMachine
- CurrentUser
- CurrentService
For each one of those you can use:
- MY
- ROOT
- TRUST
- CA
# Marks that the following is thumbprint of the certificate found in the relevant store.
You can find the thumbprint by opening the certificate and going to the details tab, there you should look for the Thumbprint field: