Thanks for reporting this.
Very likely you don’t have windows update KB3033929 installed. It is only required on windows 7.
- For 64bit system: Download from https://www.microsoft.com/en-us/download/details.aspx?id=46148
- For 32bit system: Download from https://www.microsoft.com/en-us/download/details.aspx?id=46078
Download the windows update installer, install it, and reboot your system. Then try the seadrive installer again.
We’ll improve the seadrive installer to show the exact error message to make it more clear.