Cannot start IMFlows/NetSAW2 service on Windows

After installing IMFlows, it is not accessible from InterMapper.
The IMFlows/NetSAW2 service is not started in Administration Tools > Services

When you start IMFlows service, the following message displays:

• Windows could not start the IMFlows/NetSAW2 Service service on Local Computer.
  Error 0xffffffff: 0xffffffff

1. Go into the install directory, and locate the SESSIONDB directory
The default installation directory is C:\Program Files\ns2flows
2. Remove the contents of that directory (leaving the directory itself intact).
3. Retry the Flows launch from InterMapper.

If Flows was previously installed, the path to the SESSIONDB folder will be the same as shown above.

If InterMapper 5.7 and beyond were installed without Flows having been installed previously the path will be

C:\ProgramData\InterMapper\InterMapper Settings\Flows\SESSIONDB