How do I solve "Keyword not supported: 'metadata' "?

That connection string is only supported by Entity Framework. (To be fair, the keyword "entities" is in the key name!) If you want to use the connection string in an ADO raw connection, remove anything outside the " string parts, including the "s:

Change it to:

<add name="Teleport_DEVEntities" 
  connectionString="data source=*****;initial catalog=****;integrated security=True;MultipleActiveResultSets=True;App=EntityFramework" 
  providerName="System.Data.EntityClient" 
/>

It seems the connectionString is of EntityFramework Type. Possible way could be skipping metaData and then getting the complete connectionString.

The below code saved my time !!

if (connectionString.ToLower().StartsWith("metadata=")) {
    System.Data.Entity.Core.EntityClient.EntityConnectionStringBuilder efBuilder = new System.Data.Entity.Core.EntityClient.EntityConnectionStringBuilder(connectionString);
    connectionString = efBuilder.ProviderConnectionString; }