Invalid derivative storage size given

When uploading a PDF I get the following error:

InvalidArgumentException: Invalid derivative storage size given. in /home/selkirkm/public_html/collection/application/libraries/Omeka/File/Derivative/Creator.php:99
Stack trace:
#0 /home/selkirkm/public_html/collection/application/models/File.php(352): Omeka_File_Derivative_Creator->addDerivative(‘thumbnail’, ‘0’)
#1 /home/selkirkm/public_html/collection/application/models/Job/FileProcessUpload.php(22): File->createDerivatives()
#2 /home/selkirkm/public_html/collection/application/libraries/Omeka/Job/Dispatcher/Adapter/Synchronous.php(25): Job_FileProcessUpload->perform()
#3 /home/selkirkm/public_html/collection/application/libraries/Omeka/Job/Dispatcher/Default.php(137): Omeka_Job_Dispatcher_Adapter_Synchronous->send(’{“className”:"J…’, Array)
#4 /home/selkirkm/public_html/collection/application/models/File.php(203): Omeka_Job_Dispatcher_Default->send(‘Job_FileProcess…’, Array)
#5 /home/selkirkm/public_html/collection/application/libraries/Omeka/Record/AbstractRecord.php(280): File->afterSave(Array)
#6 /home/selkirkm/public_html/collection/application/libraries/Omeka/Record/AbstractRecord.php(548): Omeka_Record_AbstractRecord->runCallbacks(‘afterSave’, Array)
#7 /home/selkirkm/public_html/collection/application/models/Item.php(336): Omeka_Record_AbstractRecord->save()
#8 /home/selkirkm/public_html/collection/application/models/Item.php(249): Item->saveFiles()
#9 /home/selkirkm/public_html/collection/application/libraries/Omeka/Record/AbstractRecord.php(280): Item->afterSave(Array)
#10 /home/selkirkm/public_html/collection/application/libraries/Omeka/Record/AbstractRecord.php(548): Omeka_Record_AbstractRecord->runCallbacks(‘afterSave’, Array)
#11 /home/selkirkm/public_html/collection/application/libraries/Omeka/Controller/AbstractActionController.php(188): Omeka_Record_AbstractRecord->save(false)
#12 /home/selkirkm/public_html/collection/application/controllers/ItemsController.php(148): Omeka_Controller_AbstractActionController->addAction()
#13 /home/selkirkm/public_html/collection/application/libraries/Zend/Controller/Action.php(516): ItemsController->addAction()
#14 /home/selkirkm/public_html/collection/application/libraries/Zend/Controller/Dispatcher/Standard.php(308): Zend_Controller_Action->dispatch(‘addAction’)
#15 /home/selkirkm/public_html/collection/application/libraries/Zend/Controller/Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))
#16 /home/selkirkm/public_html/collection/application/libraries/Zend/Application/Bootstrap/Bootstrap.php(105): Zend_Controller_Front->dispatch()
#17 /home/selkirkm/public_html/collection/application/libraries/Zend/Application.php(384): Zend_Application_Bootstrap_Bootstrap->run()
#18 /home/selkirkm/public_html/collection/application/libraries/Omeka/Application.php(73): Zend_Application->run()
#19 /home/selkirkm/public_html/collection/admin/index.php(36): Omeka_Application->run()
#20 {main}

There was no adding of any plugins or updates that triggered this, at least that I’m aware of. Uploading was working correctly, but after not touching it for a few months I went back and started getting this error.

Any help would be appreciated

There are settings under Appearance -> Settings for the dimensions of the various types of thumbnails… it seems like you might have one of them set to zero?

Palm to forehead. Thanks for the quick reply, that’s what it was.