This error message on google finds how folk are dealing with it. Maybe in a few months Microsoft will issue a patch but for now we use what others are doing or ignore it.
On every boot up I get an Alert that says, "Required System Software Not Installed.
Microsoft Net Framework version 2.0 is required to continue. This software is available for free at microsoft downloads.
My add/remove shows me that .Net v4 is installed.
When I try to install 2 (to make that alert window STOP popping up) Microsoft tells me that I have a newer version. I am very leery of UNinstalling v4, installing v2 then updating v2 to v4.