Thank you for using Bitnami, I'm going to explain here your current configuration to verify that I understood all the information you posted in your message:
- Your operating system is Windows 10
- You installed WAPP in the past but it stopped working, did you remove that installation? Did you modify any configuration files of it?
- You reinstalled the stack again but got the "Unable to install wapp as a service" error message. Could you please share with us the content of the installation log? You'll find it at:
Please note that it's a temporary folder and that's removed when restarting the machine. You will probably find some of those folders as hidden ones.
In case you didn't remove the old installation of WAPP, could you please share with us the content of the error_log file of Apache?