Run Powershell or Command Prompt as administrator during Visual Studio Team Services build - build

Question

I am working on a project where we are delay signing the assemblies. I need to use the strong name tool a couple times during the build, to turn off strong name verification, and then to fully sign the assemblies before they are packaged. I attempted to use a powershell step to turn off verification, but it came back with this error:
Script:
$testprojs = gci Project.*.dll -r
$testprojs | % {
sn -Vr $_
write-output $("Turned off sn verification for " + $_.Name)
}
Error:
Failed to open registry key -- Administrator permissions are needed to use
the selected options. Use an administrator command prompt to complete these tasks.
So I created a script that would run the first one, but added the -elevated parameter. This made no difference.
I also tried using a command prompt step instead of powershell. This also returned the same error.
For /r %g in ("Project.*.dll") DO sn -Vr %g
When I tried running this same script rdp'd to the build agent machine itself, it works as intended. It's only when it runs as a step in the build does it not work.
Any ideas?

Answer 1

According to your description:
When I tried running this same script rdp'd to the build agent machine
itself, it works as intended.
I assume you are using your own build agent for build. Then this may caused by the build agent isn't running with an administrator account. Please update your build agent to run with administrator account and then try again.
Run the agent Run as a service
If you deployed the agent to run as a Windows service, then the agent
running status can be controlled from the Services snap-in. Run
services.msc and look for "VSO Agent ()". If you
need to change the logon account, don't do it from the services
snap-in. Instead, From an elevated Command Prompt, run:
C:\Agent\Agent\VsoAgent.exe /ChangeWindowsServiceAccount Run
interactively
Otherwise if you installed the agent to run interactively, the agent
can be started by launching Agent\VsoAgent.exe.
Refer to this link for details: Run the agent