Error code 30015 notification while installing office programs in the latest windows 10 or windows 11. There are various reasons to discuss and important ones of them are due to registry corruption. This issue pops up when there is a problem to access restrictions to the installation source. This can be due to the partially downloaded office source files. Incomplete office download happens due to the internet issues or space related issues.
https://www.officelivesupport.com/microsoft-office-error-code-30015/