Since we have installed the June CU on our farm we get an "Unknown Error" while creating the default groups of a subsite (permsetup.aspx). ULS LogViewer shows me the following Exception: Exception Type: System.FormatException Exception Message: String was not recognized as a valid Boolean.
The error only occurs if a radio button is changed on the permsetup page. If we are taking the default settings (existing group for visitors, new group for members and owners) everything works fine and the groups are created.
Is there a known fix for this issue?