Summary:  While configuring the Salesforce on the step to generate token we get the error "Invalid JSON primitive" and "This command cannot be run due to the error: The system cannot find the file specified"  or The remote name could not be resolved: 'login.salesforce.com' 
Symptoms:

The cause is that the Salesforce URL needs to contain your company's personal access address, for example, "https://mycompanyname.salesforce.com".

 On the regular Salesforce login page, that message seems to appear when the account that was logged in either timed out or was logged out while the URL is still trying to access a page. 

The most common cause is that there is no Internet connection available on the machine the inventory beacon software is installed on. There may be other reasons such as Salesforce.com being blocked or is currently down.

Steps to Follow while creating a Salesforce Connection:

1. Log in to Salesforce and create a connected app. (A connected app is required for a connection to Salesforce.com on the FlexNet Beacon to work.) For information about how to create a connected app in Salesforce, see https://help.salesforce.com/articleView?id=connected_app_create.htm.

2. Note the following:

   When creating the connected app, ensure that you select Enable OAuth Settings, select the Enable for Device Flow check box and select all Available OAuth Scopes. The connected app in Salesforce uses standard SAML and OAuth protocols to authenticate, provide single sign-on, and provide tokens for use with Salesforce APIs. In addition to standard OAuth capabilities, connected apps allow Salesforce admins to set various security policies and have explicit control over who can use the corresponding apps. After creating the connected app in Salesforce, you can view the app details in order to copy and paste the Consumer Key and Consumer Secret values to the corresponding fields in the FlexNet Beacon PowerShell Source Connection dialog.

3. Log in to Salesforce and access the connected app to view details.

Token Generation:

When you click Generate to the right of the Refresh Token field, a Web browser is launched in Salesforce.com with an 8-digit code automatically populated in the Code field. In the Salesforce.com screen, do the following:

1. Click Connect. A Salesforce login page displays. If you are already logged into Salesforce.

2. Enter your Salesforce username. If there are multiple Salesforce accounts, select your username from the Saved Username list or click Log In with a Different Username. A Password field appears.

3. In the Password field, enter your Salesforce password.

4. Click Login. An Allow Access page appears.

5. Click Allow to allow Salesforce to access the FlexNet Beacon to have the refresh token sent back to PowerShell Source Connection dialog. A message appears to notify you that the connection is successful. Click Continue or close the browser.