If you get this error, your keyword-driven test does not include a Start application keyword as the first keyword. Silk Test requires the Start application keyword to apply the application configuration of your project to the keyword-driven test. When you record a new keyword-driven test in Silk Test, Silk Test automatically adds the Start application keyword as the first keyword to the keyword-driven test.
With Silk Test 19.5 or later, parallel testing is enabled by default. When you upgrade from a Silk Test version prior to Silk Test 19.5 to a more recent Silk Test version, previously executing keyword-driven tests might no longer execute because each individual test is now expected to specify the application under test (AUT).
To workaround this issue, disable parallel testing on the machine on which Silk Test is running by setting the environment variable SILK_TEST_ENABLE_PARALLEL_TESTING to false.