Hi,
Are you trying to import an application in the server as a LCA? Have you checked whether that application was existing previously or not? Sometimes if the application archieve is corrupted this type of situation might happen. Another reason might be you have already deployed application of the same name. try to undeploy the application if you have in the same name and try doing it. You can also import that in thw orkbench if you have got individual files.
Thanks,
Bibhu.