i installed windoblind and it said my key is invalid

Hello,
Sorry to hear you are having issues. Look like you're having account issue, please raise support ticket using the link below, use the "Ask a Question" option. Include all information details. Remember to record down the ticket number for future reference if needed. Do not raise multiple ticket, that will make your ticket back to the end of the line. Send once and wait. Ticket will be answer by the order they send in.

https://stardock.atlassian.net/servicedesk/customer/portal/4/group/13 

Thanks
Basj,
Stardock Community Assistant