To install the .PFX certificate, please follow the steps below.
1. First you need to convert the .pfx type to .truststore type. To do that, place the .pfx file under \OpManager\jre\bin folder. Also open a command prompt as Administrator and go to \OpManager\jre\bin folder.
2. Run the command below with the correct .pfx file.
keytool.exe -importkeystore -srckeystore mykeystore.pfx -destkeystore OpManager.truststore -srcstoretype pkcs12 -deststoretype JKS
It will ask you for a password, please use the pfx password as the truststore password.
3. OpManager.truststore file will be generated after running the above command under \OpManager\jre\bin folder, place this file under \OpManager\conf folder.
4. Now we have to configure Tomcat, for that, open "ssl_server.xml" file (under OpManager_Home\tomcat\conf\backup) in a text editor. Search for term "keystoreFile". It will be an attribute for connector tag. And set the value as "WEBNMS_ROOT_DIR/conf/OpManager.truststore". Change the value for "keystorePass" attribute with your keystore file password.
5. Edit the OpManagerStartUp.properties file under \OpManager\conf folder. Set the value of the parameter "https" as "Enable" and save it.
6. Start OpManager.
For enabling SSL in OpManager and to import third party certificates, please check this article.