We are having the same problem on several of our machines. Upon machine startup, the Windows Installer pops up and says:
"The feature you are trying to use is on a network resource that is unavailable. Click OK to try again, or enter an alternate path to a folder containing the installation package "IBM Notes 9.0.1 Social Edition.msi" in the box below."
And, like the user above is experiencing, the default source points to c:\users\username\appdata\local\temp\etc. All users are on the latest Windows 10 and IBM Notes 9.0.1 FP6 and above.
Just started yesterday morning, July 9, 2018. Any help is greatly appreciated.