v3 RC1 , secure.dll error.

I have installed RC1 via FTP on RB133, well no problems on installing & booting , can connect via serial but, when i try to log in via winbox i face an error “could not locate secure.dll” and quits. Secure mode on winbox is not selected, (tried to select and login) nothing chaged. anyone experienced with same problem ??

delete winbox files in your users directory and try again. (somewhere under Application Data)

Sometimes AFAIK this is necessary on production releases too.
I button or routine “cleanse old WinBox files” would be useful, because though an expert knows what to do, an end-user doesn’t always. Would be helpful IMHO.