On your list I don't see seting up the database as trustworthy, so I assume that you forgot this step:
ALTER DATABASE my_db_name SET TRUSTWORTHY ON;
But maybe not...
Checking with this article: http://support.microsoft.com/kb/918040 it seems that they indeed sugest using sp_changedbowner instead of ALTER AUTHORIZATION. But the fact is, it does exactly the same thing (sp_changedbowner calls ALTER AUTHORIZATION under the covers). The difference is that it also removes "aliases" for the dbo user (deprecated functionality anyway) plus forces a checkpoint of the database.
That last piece may be the one you are looking for.
There doesn't appear to be a GUI-based way of doing this unless you're joined to a domain - at least not one I could find anywhere - so I did a bit more digging and I've found an answer that works for our situation.
I didn't understand what the string representation meant in the knowledge base article, but doing a bit of digging led me to discover that it's SDDL syntax. Further digging led me to this article by Alun Jones which explains how to get the security descriptor for a service and what each bit means. MS KB914392 has more details.
To append to the service's existing security descriptor, use sc sdshow "Service Name" to get the existing descriptor. If this is a plain old .NET Windows Service - as is the case with ours - the security descriptor should look something like this:
D:(A;;CCLCSWRPWPDTLOCRRC;;;SY)(A;;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;BA)(A;;CCLCSWLOC
RRC;;;IU)(A;;CCLCSWLOCRRC;;;SU)(A;;CR;;;AU)(A;;CCLCSWRPWPDTLOCRRC;;;PU)S:(AU;FA
;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;WD)
We needed to grant permissions RP (to start the service), WP (to stop the service), DT (to pause/continue the service) and LO (to query the service's current status). This could be done by adding our service account to the Power Users group, but I only want to grant individual access to the account under which the maintenance service runs.
Using runas to open a command prompt under the service account, I ran whoami /all which gave me the SID of the service account, and then constructed the additional SDDL below:
(A;;RPWPDTLO;;;S-x-x-xx-xxxxxxxxxx-xxxxxxxxxx-xxxxxxxxx-xxxx)
This then gets added to the D: section of the SDDL string above:
D:(A;;CCLCSWRPWPDTLOCRRC;;;SY)(A;;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;BA)(A;;CCLCSWLOC
RRC;;;IU)(A;;CCLCSWLOCRRC;;;SU)(A;;CR;;;AU)(A;;CCLCSWRPWPDTLOCRRC;;;PU)(A;;RPWP
DTLO;;;S-x-x-xx-xxxxxxxxxx-xxxxxxxxxx-xxxxxxxxx-xxxx)S:(AU;FA;CCDCLCSWRPWPDTLOC
RSDRCWDWO;;;WD)
This is then applied to the service using the sc sdset command (before the S: text):
sc sdset "Service Name" D:(A;;CCLCSWRPWPDTLOCRRC;;;SY)(A;;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;BA)(A;;
CCLCSWLOCRRC;;;IU)(A;;CCLCSWLOCRRC;;;SU)(A;;CR;;;AU)(A;;CCLCSWRPWPDTLOCRRC;;;PU
)(A;;RPWPDTLO;;;S-x-x-xx-xxxxxxxxxx-xxxxxxxxxx-xxxxxxxxx-xxxx)S:(AU;FA;CCDCLCSW
RPWPDTLOCRSDRCWDWO;;;WD)
If all goes according to plan, the service can then be started, stopped, paused and have it's status queried by the user defined by the SID above.
Best Answer
I'm not sure what you've tried to do before, but here's what I just did and had success:
1) Downloaded the Tomcat 5.5.27 Windows Service installer and installed it.
2) Dumped the TomCat5 service security descriptor using "sc sdshow tomcat5", which showed me:
This is a pretty common security descriptor for services. I've seen it verbatim on some Microsoft services. The SYSTEM and built-in Administrators have "full control", "Power Users" can stop, start, and pause the service, and "Authenticated Users" can query properties of the service (I'm glossing over a bit here).
3) I created a limited user called "bob" on my box, opened a "RUNAS" command-prompt as him, and got his SID from "WHOAMI /ALL" (a command that's on Windows Server 2003 but not on XP... don't know about Vista and Windows 7 off the top of my head). I verified that Bob could not stop / start the Tomcat service (using "NET STOP tomcat5"). I received the same error you report in your post.
4) From my regular administrator command-prompt, ran the following:
This SDDL string gives Bob's SID (S-1-5-21-1409082233-484763869-854245398-1009) rights to stop, start, and pause the service (RP, WP, and DT, respectively).
5) I flipped back to my "Bob" command prompt and verified that I could now stop and start the service using NET STOP and NET START.
I'd recommend creating a group to delegte this right to, putting a user in that group, getting the group's SID (using WHOAMI or any other tool) and modifying the security descriptor this way.
I would think that using Group Policy to modify the security descriptor would work fine. I have seen cases where some services don't like the default permission that a group policy-based modification puts on a service (look at this posting about the Windows Search service if you want to see what I'm talking about: http://peeved.org/blog/2007/12/07), but that has been uncommon in my experience.
If you want more background on security descriptors for services, have a look at http://msmvps.com/blogs/alunj/archive/2006/02/13/83472.aspx and http://support.microsoft.com/kb/914392.