Note: For ExtraFax 5.0 for Exchange, you must use JDK 21 (64 bit). JDK 22 or above is not supported. ExtraFax for Exchange 5.0 (or above) has a prerequisite of JDK 21 (64 bit) (either Amazon Corretto 21 or Oracle JDK 21). It is recommended that the auto update feature of Oracle Java be disabled to avoid unexpected interference with the ExtraFax server. In case you need to update the Java JDK, we recommend you to do it manually (i.e. manually un-install old version JDK and then install new version JDK) when the ExtraFax server is scheduled to be offline for maintenance. The reason is that the file path of JDK often contains a minor version number in it (e.g. C:\Program Files\Amazon Corretto\jdk21.0.7_6), which may get changed after the update of Java JDK. This may impact the normal operations of ExtraFax for Exchange. Therefore, it is advised to follow the steps below to update the Java JDK manually and make sure ExtraFax server is referencing the correct Java JDK path after the update. Suggested steps to update Java JDK on the ExtraFax for Exchange server: 1. Open "ExtraFax Management Console" and select "Stop All" to stop all ExtraFax services. 2. Uninstall the old version Java JDK. 3. Install the new version Java JDK manually. 4. Important: Close and restart the "ExtraFax Management Console" so that it will update the "javahome" parameter in the extrafax.cfg automatically. 5. Make sure the "Java Runtime" path displayed in the "ExtraFax Management Console" is the correct one. 6. Select "Start All" in the "ExtraFax Management Console" to start all ExtraFax services: 7. Send a test fax and see whether the fax is successfully sent.