OHMS import error in the log file

[hkaouri]

I am getting the following error in the log file while importing xml file from OHMS:
OHMS file must be validated before retrieving list of column examples. in /home/aukoralh/public_html/plugins/OhmsImport/models/OhmsImport/File.php:62
what could be the cause?

[alehandrof]

I get the same error:

LogicException: OHMS file must be validated before retrieving list of column examples. in /home/amicalre/public_html/omeka-armstrong/plugins/OhmsImport/models/OhmsImport/File.php:62
Stack trace:
#0 /home/amicalre/public_html/omeka-armstrong/plugins/OhmsImport/controllers/IndexController.php(182): OhmsImport_File->getColumnExamples()
#1 /home/amicalre/public_html/omeka-armstrong/application/libraries/Zend/Controller/Action.php(516): OhmsImport_IndexController->indexAction()
#2 /home/amicalre/public_html/omeka-armstrong/application/libraries/Zend/Controller/Dispatcher/Standard.php(308): Zend_Controller_Action->dispatch('indexAction')
#3 /home/amicalre/public_html/omeka-armstrong/application/libraries/Zend/Controller/Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))
#4 /home/amicalre/public_html/omeka-armstrong/application/libraries/Zend/Application/Bootstrap/Bootstrap.php(105): Zend_Controller_Front->dispatch()
#5 /home/amicalre/public_html/omeka-armstrong/application/libraries/Zend/Application.php(384): Zend_Application_Bootstrap_Bootstrap->run()
#6 /home/amicalre/public_html/omeka-armstrong/application/libraries/Omeka/Application.php(73): Zend_Application->run()
#7 /home/amicalre/public_html/omeka-armstrong/admin/index.php(28): Omeka_Application->run()
#8 {main}