silk test 18.5 gives no response while executing vb.net script from visual test

 silk test was working before to run the visual tests calling shared vb scripts successfully but suddenly it hangs without getting any response or error

I tried to restart silktest service

i tried to reinstall siilktest 18.5 and hotfix 1

I tried to rollback all windows changes

reinstall the java JDK to version 8 build 144

so kindly advise with other solutions as it is critical