IIS requires a .pfx format to import. I will show you two commands
Command to export a SSL certificate from Tomcat to IIS
keytool -importkeystore -srckeystore certificates.ks -srcstoretype JCEKS -destkeystore jordansphere.pfx -deststoretype PKCS12
Note: You'll need the original keystore password for the export.
Command to export a SSL certificate from Apache to IIS
openssl pkcs12 -export -out jordansphere.pfx -inkey jordansphere_cert.key -in jordansphere_cert.pem