See this guide https://www.manager.io/guides/22936
Manager defaults to installing the program in an individual users appdata\roaming\manager directory not c:\program files (x86)\manager
It appears you have previously installed Manager on the f: drive and the installer is having trouble finding the old version to uninstall.
Btw if you want to install Manager in c:\program files (x86)\manager run the installer from an elevated command prompt to comply with UAC requirements. See this thread for more information