title: Magento “Cannot add the item to shopping cart.” For no apparent reason
body: <p>I have a slightly strange problem that I need your help with.</p>
  
  <p>I have three independent Magento installations on my server. Two of which under an SSL certificate as such: https ://apps.domain.com/store1 &amp; https ://apps.domain.com/store2. Both of these stores how custom themes. The third installation is a fresh install on the root of the domain without an SSL certificate as such: http:// www.domain.com/store3</p>
  
  <p>What happens is that, all of a sudden, all three stores stop being able to add items to cart and give me this error "Cannot add the item to shopping cart.". And then an hour or a couple of hours later or so, the add to cart buttons start working again. The weird thing is that I don't change anything to make it work or stop working, and they all work or stop working simultaneously.</p>
  
  <p>Please advise!</p>
  
  <p><strong>Update</strong>:</p>
  
  <p>Actually I found this in my exception log:
  <code></p>
  
  <pre><code>2014-07-27T21:09:35+00:00 DEBUG (7): Exception message: Notice: Undefined offset: 2  in /home/---/store2/lib/Zend/Locale/Format.php on line 577
  Trace: #0 /home/---/store2/lib/Zend/Locale/Format.php(577): mageCoreErrorHandler(8, 'Undefined offse...', '/home/vmegypt/p...', 577, Array)
  1 /home/---/store2/lib/Zend/Locale/Format.php(513): Zend_Locale_Format::_getRegexForType('decimalnumber', Array)
  2 /home/---/store2/lib/Zend/Filter/LocalizedToNormalized.php(100): Zend_Locale_Format::isNumber('3', Array)
  3 /home/---/store2/app/code/core/Mage/Checkout/controllers/CartController.php(187): Zend_Filter_LocalizedToNormalized-&gt;filter('3')
  4 /home/---/store2/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Checkout_CartController-&gt;addAction()
  5 /home/---/store2/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(250): Mage_Core_Controller_Varien_Action-&gt;dispatch('add')
  6 /home/---/store2/app/code/core/Mage/Core/Controller/Varien/Front.php(172): Mage_Core_Controller_Varien_Router_Standard-&gt;match(Object(Mage_Core_Controller_Request_Http))
  7 /home/---/store2/app/code/core/Mage/Core/Model/App.php(354): Mage_Core_Controller_Varien_Front-&gt;dispatch()
  8 /home/---/store2/app/Mage.php(683): Mage_Core_Model_App-&gt;run(Array)
  9 /home/---/store2/index.php(117): Mage::run('', 'store')
  10 {main}
  2014-07-27T21:09:35+00:00 ERR (3): 
  exception 'Exception' with message 'Notice: Undefined offset: 2  in /home/---/store2/lib/Zend/Locale/Format.php on line 577' in /home/---/store2/app/code/core/Mage/Core/functions.php:245
  Stack trace:
  0 /home/---/store2/lib/Zend/Locale/Format.php(577): mageCoreErrorHandler(8, 'Undefined offse...', '/home/vmegypt/p...', 577, Array)
  1 /home/---/store2/lib/Zend/Locale/Format.php(513): Zend_Locale_Format::_getRegexForType('decimalnumber', Array)
  2 /home/---/store2/lib/Zend/Filter/LocalizedToNormalized.php(100): Zend_Locale_Format::isNumber('3', Array)
  3 /home/---/store2/app/code/core/Mage/Checkout/controllers/CartController.php(187): Zend_Filter_LocalizedToNormalized-&gt;filter('3')
  4 /home/---/store2/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Checkout_CartController-&gt;addAction()
  5 /home/---/store2/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(250): Mage_Core_Controller_Varien_Action-&gt;dispatch('add')
  6 /home/---/store2/app/code/core/Mage/Core/Controller/Varien/Front.php(172): Mage_Core_Controller_Varien_Router_Standard-&gt;match(Object(Mage_Core_Controller_Request_Http))
  7 /home/---/store2/app/code/core/Mage/Core/Model/App.php(354): Mage_Core_Controller_Varien_Front-&gt;dispatch()
  8 /home/---/store2/app/Mage.php(683): Mage_Core_Model_App-&gt;run(Array)
  9 /home/---/store2/index.php(117): Mage::run('', 'store')
  10 {main}
  </code></pre>
  
  <p></code></p>