MSDE in registry ?

Hello. I have the question.
Now i am writing the tool that clear my instance registry values if
install of msde failed.
How to determine is any msde instance installed ?
Is it enough to know that in
HKLM\software\microsoft\microsoft sql server\component set
is exist {productcode} and in
HKLM\software\microsoft\microsoft sql server\my instance\setup
is exist productcode field with {productcode} value ?.This might be helpful:
http://support.microsoft.com/kb/290991/en-us
--
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Alexander" <alt7@.douweb.org> wrote in message
news:1147973979.884581.6850@.y43g2000cwc.googlegroups.com...
> Hello. I have the question.
> Now i am writing the tool that clear my instance registry values if
> install of msde failed.
> How to determine is any msde instance installed ?
> Is it enough to know that in
> HKLM\software\microsoft\microsoft sql server\component set
> is exist {productcode} and in
> HKLM\software\microsoft\microsoft sql server\my instance\setup
> is exist productcode field with {productcode} value ?.
>