I got it from the Ricoh site:
https://theta360.com/en/support/faq/c_06_v/304_1/
https://theta360.com/en/support/download/liveapp4k/win64
https://theta360.com/en/support/download/liveapp4k/win32
I think you’ll need the driver for most applications. You can try calling Ricoh customer support if you’re having problems or suspect a virus in it.
There’s a long discussion thread here about people needing to use the driver.