Hello,
I have not used Sql server.
I have microsoft sql server 2008 installed. but when i click management studio, it says evaluation period expired.
I can download sql server 2008 r2 developer from my university site.
Should i go ahead and download sql server 2008 r2 developer and uninstall microsoft sql server 2008? what is difference in both?

i am installing sql server 2008 r2.
I found the error at server configuration as:
1)the specified credential that are specified are not valid.to continue provide account and password for SQL server service..
2)the specified credential that are specified are not valid.to continue provide account and password for analysis services service.
3)the specified credential that are specified are not valid.to continue provide account and password for reporting services service.
i can not go ahead.
what to do? please help.

i am installing sql server 2008 r2.
I found the error at server configuration as:
1)the specified credential that are specified are not valid.to continue provide account and password for SQL server service..
2)the specified credential that are specified are not valid.to continue provide account and password for analysis services service.
3)the specified credential that are specified are not valid.to continue provide account and password for reporting services service.
i can not go ahead.
what to do? please help.