Modifying the "Path to executable" of a windows service

You could also do it with PowerShell:

Get-WmiObject win32_service -filter "Name='My Service'" `
    | Invoke-WmiMethod -Name Change `
    -ArgumentList @($null,$null,$null,$null,$null, `
    "C:\Program Files (x86)\My Service\NewName.EXE")

Or:

Set-ItemProperty -Path "HKLM:\System\CurrentControlSet\Services\My Service" `
    -Name ImagePath -Value "C:\Program Files (x86)\My Service\NewName.EXE"

There is also this approach seen on SuperUser which uses the sc command line instead of modifying the registry:

sc config <service name> binPath= <binary path>

Note: the space after binPath= is important. You can also query the current configuration using:

sc qc <service name>

This displays output similar to:

[SC] QueryServiceConfig SUCCESS

SERVICE_NAME: ServiceName

    TYPE               : 10  WIN32_OWN_PROCESS
    START_TYPE         : 2   AUTO_START
    ERROR_CONTROL      : 1   NORMAL
    BINARY_PATH_NAME   : C:\Services\ServiceName
    LOAD_ORDER_GROUP   :
    TAG                : 0
    DISPLAY_NAME       : <Display name>
    DEPENDENCIES       :
    SERVICE_START_NAME : user-name@domain-name

It involves editing the registry, but service information can be found in HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services. Find the service you want to redirect, locate the ImagePath subkey and change that value.