Hello Yugain,
Are you using a keystore with WS Security?
If yes, verify the path provided and try with different slashes (/ - \).
You can also create a MAR info file for the test case or VSM by right click on the test case/VSM and select "Create MAR info file". Check whether security token details (keystore/jks files) are included in mari file. If not included, you can try to add those details manually or place the keystore in the PROJECT_ROOT/Data folder, update the step and recreate the mari file.
Once you verify the keystore is available in the MARinfo file you can create the MAR file from mari (right click on mari file and select "Create MAR file").
Once MAR file is created, you can run/deploy it.
Hope it helps.
Heloisa