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The main reason behind it there was no form_key for the login form and there is a form key validation taking place in loginPostAction of Magento. For solving such kind of problem use the steps below:
Step 1. Open the login.phtml in your favourite file editor, for this navigate to the app/design/frontend/base/default/template/customer/form/login.phtml and app/design/frontend/base/default/template/persistent/customer/form/login.phtml or find it if you are using the custom template app/design/frontend/default/your_custom_theme/template/customer/form/login.phtml and app/design/frontend/default/your_custom_theme/template/persistent/customer/form/login.phtml
Step 2. Search for
<ul class="form-list">
Step 3. Add the below code under
<ul class="form-list">
<input type="hidden" name="form_key" value="<?php echo Mage::getSingleton('core/session')->getFormKey(); ?>" />
The code will look like as the below:
<ul class="form-list">
<input type="hidden" name="form_key" value="<?php echo Mage::getSingleton('core/session')->getFormKey(); ?>" />
Save the file and run the code, problem has been gone
Note : Use same code for the other custom login form if you are using.
Hope it helps, Thanks for reading.
