How to manually uninstall SQL Server 2008 R2 completely

> Setup of SQL Server failed.
> The following error occurred during setup of SQL Server:
> The state of your SQL Server installation was not changed after the setup execution. Please review
> The summary.txt logs for further details.
> Error code 0x84B30002.
> [OK]



○
"C: \ Program Files \ Microsoft SQL Server \ 100 \ Setup Bootstrap \ Log \ summary.txt"
→ Unknown even if you look at it

○ Check the registry
"HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Uninstall"
From here, search by "SQL" and judge by "DisplayName".
Uninstall with that GUID

○ Uninstall command
Msiexec / x "{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}"
(Enter the GUID to uninstall)


○ Delete files
Erase all "C: \ Program Files \ Microsoft SQL Server" directory

"C: \ Documents and Settings \ Administrator \ Local Settings \ Application Data \ Microsoft \ Microsoft SQL Server"
"C: \ Documents and Settings \ Administrator \ Application Data \ Microsoft \ Microsoft SQL Server"
There is also a file here.

○ Confirmation
From "SQL Server Installation Center", go to "Maintenance"-> "Repair" and proceed
As it is not installed, "Product key" of "SQL Server 2008 R2 setup" should be displayed.

If another screen like repair appears, I can not uninstall completely.


If instances remain and can not be reinstalled
It's a memo, as it will be awkward as SQL gets stuck.