[Error Code]

I have the same problem. I downloaded some games images and launchbox will not start anymore and come up with this  message:

"System.ArgumentException: An item with the same key has already been added"

i purchased the license from the premium page and i never shared it with anyone.
   

[Launchbox Premium member... updated and now Big Box won't open]

hawkguy said Hey Jason, I never figured this out. But 6.2 finally installed correctly after trying ever past and present version that I have. No idea what the issue was but 6.2 seems to have fixed it.

Updated to 6.2 and bigbox is working... thanks

[Launchbox Premium member... updated and now Big Box won't open]

I'm having the same problem, and when i hit ignore Bitdefender antivirus will delete BigBox.exe Virus: Gen:Variant.Razy.55596 even after i make exclusion for this file it will be deleted... i didn't have this problem with old version PS: I just installed ver 5.9 without any problems :)