msde installation invalid instance name

while installing msde desktop sp3 it gives error invalid instance name what should i do to resolve it
Do you already have an instance (of SQL Server or MSDE) installed?
If so, you'll need to identify a new instance name for your new
installation:
"..\setup.exe INSTANCENAME=whatever ..."
You need to issues this command via the command window or you can setup a
shortcu for this.
Also, if you have installed and instance and can't access it from clients,
run SVRNETCN.exe and make sure that you have at least one protocol enabled
(e.g. TCP/IP or Multi Protocol). If no protocols are enabled, clients won't
be able to access it.
Hope this helps,
Joe Geretz
"pink" <anonymous@.discussions.microsoft.com> wrote in message
news:E2E88A6D-5E7C-467E-9764-B6DA962F7C7A@.microsoft.com...
> while installing msde desktop sp3 it gives error invalid instance name
what should i do to resolve it