title: Product page: There has been an error processing your request
body: <p>I've recently upgraded to Magento 1.9. After solving some problems, I couldn't find a solution for this issue. </p>
  
  <p>Magento throws the following error when trying to navigate to a product page: </p>
  
  <pre><code>There has been an error processing your request
  Invalid method DerModPro_BasePrice_Block_Catalog_Product_View_Type_Simple::displayProductStockStatus(Array
  (
  )
  )
  
  Trace:
  #0 /kunden/329924_40211/magento19/app/design/frontend/tm_themes/theme350k/template/catalog/product/view/type/availability/default.phtml(27): Varien_Object-&gt;__call('displayProductS...', Array)
  #1 /kunden/329924_40211/magento19/app/design/frontend/tm_themes/theme350k/template/catalog/product/view/type/availability/default.phtml(27): DerModPro_BasePrice_Block_Catalog_Product_View_Type_Simple-&gt;displayProductStockStatus()
  #2 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(241): include('/kunden/329924_...')
  #3 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(272): Mage_Core_Block_Template-&gt;fetchView('frontend/tm_the...')
  #4 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(286): Mage_Core_Block_Template-&gt;renderView()
  #5 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(923): Mage_Core_Block_Template-&gt;_toHtml()
  #6 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(641): Mage_Core_Block_Abstract-&gt;toHtml()
  #7 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(585): Mage_Core_Block_Abstract-&gt;_getChildHtml('product_type_av...', true)
  #8 /kunden/329924_40211/magento19/app/design/frontend/tm_themes/theme350k/template/catalog/product/view.phtml(95): Mage_Core_Block_Abstract-&gt;getChildHtml('product_type_av...')
  #9 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(241): include('/kunden/329924_...')
  #10 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(272): Mage_Core_Block_Template-&gt;fetchView('frontend/tm_the...')
  #11 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(286): Mage_Core_Block_Template-&gt;renderView()
  #12 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(923): Mage_Core_Block_Template-&gt;_toHtml()
  #13 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Text/List.php(43): Mage_Core_Block_Abstract-&gt;toHtml()
  #14 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(923): Mage_Core_Block_Text_List-&gt;_toHtml()
  #15 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(641): Mage_Core_Block_Abstract-&gt;toHtml()
  #16 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(585): Mage_Core_Block_Abstract-&gt;_getChildHtml('content', true)
  #17 /kunden/329924_40211/magento19/app/design/frontend/tm_themes/theme350k/template/page/2columns-left.phtml(70): Mage_Core_Block_Abstract-&gt;getChildHtml('content')
  #18 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(241): include('/kunden/329924_...')
  #19 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(272): Mage_Core_Block_Template-&gt;fetchView('frontend/tm_the...')
  #20 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Template.php(286): Mage_Core_Block_Template-&gt;renderView()
  #21 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Block/Abstract.php(923): Mage_Core_Block_Template-&gt;_toHtml()
  #22 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Model/Layout.php(555): Mage_Core_Block_Abstract-&gt;toHtml()
  #23 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Controller/Varien/Action.php(390): Mage_Core_Model_Layout-&gt;getOutput()
  #24 /kunden/329924_40211/magento19/app/code/core/Mage/Cms/Helper/Page.php(137): Mage_Core_Controller_Varien_Action-&gt;renderLayout()
  #25 /kunden/329924_40211/magento19/app/code/core/Mage/Cms/Helper/Page.php(52): Mage_Cms_Helper_Page-&gt;_renderPage(Object(Mage_Cms_IndexController), 'no-route')
  #26 /kunden/329924_40211/magento19/app/code/core/Mage/Cms/controllers/IndexController.php(75): Mage_Cms_Helper_Page-&gt;renderPage(Object(Mage_Cms_IndexController), 'no-route')
  #27 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Cms_IndexController-&gt;noRouteAction()
  #28 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(254): Mage_Core_Controller_Varien_Action-&gt;dispatch('noRoute')
  #29 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Controller/Varien/Front.php(172): Mage_Core_Controller_Varien_Router_Standard-&gt;match(Object(Mage_Core_Controller_Request_Http))
  #30 /kunden/329924_40211/magento19/app/code/core/Mage/Core/Model/App.php(381): Mage_Core_Controller_Varien_Front-&gt;dispatch()
  #31 /kunden/329924_40211/magento19/app/Mage.php(687): Mage_Core_Model_App-&gt;run(Array)
  #32 /kunden/329924_40211/magento19/index.php(83): Mage::run('', 'store')
  #33 {main}
  </code></pre>
  
  <p>I know that the problem is happening because of the new theme i just installed (theme350k). </p>
  
  <p>Does anyone have an idea why this occurs? </p>
  
  <p>Thanks</p>