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];

If you're going across machines, you either need to be using NETWORK SERVICE, LOCAL SYSTEM, a domain account, or a SQL 2008 R2 (if you have it) Managed Service Account (which is my preference if you had such an infrastructure). You can not use an account which is not visible to the Active Directory domain.