I can't say anything about the OP's system, but I've created protected folders on other drives via Controlled Folder Access and the installer won't let me change the install location. This is unacceptable. I just bought Start11 today, so I'll give you 2 days to figure something out before I file for a refund.
End of MasterZoen's quote
The locations you have created are probably not considered secure by Windows (see https://docs.microsoft.com/en-us/windows/security/threat-protection/security-policy-settings/user-account-control-only-elevate-uiaccess-applications-that-are-installed-in-secure-locations)
Only the following locations are considered secure by Windows.
- \Program Files\ including subdirectories
- \Windows\system32\
- \Program Files (x86)\ including subdirectories for 64-bit versions of Windows
Note that secure and protected may be different things. Protecting a folder for example from ransomware wouldn't make it a secure folder.
Installation into program files is normal and considered good practice and Start11 is hardly massive.
We do offer trial versions for people to try before they purchase.
Technically you could install into program files and then move the installation and register the service using Start11Srv -install from the new location (elevated command prompt), but be aware there may be negative consequences from doing this in terms of security.