Note: For ExtraFax 5.0 for Exchange, you must use JDK 21 (64 bit). JDK 22 or above is not supported. Yes, you can use Amazon Corretto 21 (64 bit) JDK during the installation of ExtraFax 5.0 for Exchange. 1. For new installation of ExtraFax for Exchange During the installation of ExtraFax for Exchange, you will be asked to install JDK 21 (64 bit). At this time, you can download and install Amazon Corretto 21 (64 bit) JDK. Download Amazon Corretto 21 JDK (Windows x64) msi installation file (NOT zip file) in the following page and install it: https://docs.aws.amazon.com/corretto/latest/corretto-21-ug/downloads-list.html 2. For existing installation of ExtraFax for Exchange If you have already installed ExtraFax for Exchange 5.0 (and Oracle JDK 21 (64 bit) has been installed before), and now you want to switch to Amazon Corretto 21 JDK (64 bit), follow the steps here to uninstall existing Oracle JDK 21 (64 bit) and then install Amazon Corretto JDK 21 (64 bit) i. Open "ExtraFax Managment Console" and select "Stop All" to stop all ExtraFax services: ii. Download Amazon Corretto 21 JDK (Windows x64) msi installation file (NOT zip file) in the following page: https://docs.aws.amazon.com/corretto/latest/corretto-21-ug/downloads-list.html iii. Uninstall existing Oracle JDK 21 (64 bit) in the Control Panel. iv. Install "Amazon Corretto 21 JDK" by running the downloaded msi file. v. Close and restart "ExtraFax Management Console" so that it updates the Java path in the extrafax.cfg automatically. vi. Check whether the path of "Java Runtime" is updated (e.g. C:\Program Files\Amazon Corretto\jdk21.0.7_6). vii. Use notepad to open "c:\Extracomm\ExtraFax for Exchange\extrafax.cfg" and check whether the "javahome" path is updated: viii. Open "ExtraFax Managment Console" and select "Start All" to start all ExtraFax services: ix. Send a test fax and see whether the fax is successfully sent. x. Done.