Add IIS 7 AppPool Identities as SQL Server Logons

The "IIS APPPOOL\AppPoolName" will work, but as mentioned previously, it does not appear to be a valid AD name so when you search for it in the "Select User or Group" dialog box, it won't show up (actually, it will find it, but it will think its an actual system account, and it will try to treat it as such...which won't work, and will give you the error message about it not being found).

How I've gotten it to work is:

1. In SQL Server Management Studio, look for the Security folder (the security folder at the same level as the Databases, Server Objects, etc. folders...not the security folder within each individual database)
2. Right click logins and select "New Login"
3. In the Login name field, type IIS APPPOOL\YourAppPoolName - do not click search
4. Fill whatever other values you like (i.e., authentication type, default database, etc.)
5. Click OK

As long as the AppPool name actually exists, the login should now be created.

CREATE LOGIN [IIS APPPOOL\MyAppPool] FROM WINDOWS;CREATE USER MyAppPoolUser FOR LOGIN [IIS APPPOOL\MyAppPool];

You can solve like this,

1. Open "Applications Pools",
2. You should right click that you have choosed application pool. Then choose"Advanced Settings".
3. Click three point on the Identity tab then you should choose "LocalSystem" from field of "Built-in-account"

If you do this way, you don't need to create a user in database.