powershell WMI error: "Could not obtain SQL Server Service information. An attempt to connect to WMI ... failed with the following error: access is denied."

I get the following error when I launch powershell from SSMS, after right-clicking on a remote SQL instance and choosing "Start powershell":[quote]Warning: Could not obtain SQL Server Service information. An attempt to connect to WMI on server1 failed with the following error: access is denied.[/quote]How can I fix this?