Magento: There has been an error processing your request. Exception printing is disabled by default for security reasons

Problem:

I am using Magento 1.4. Homepage loads fine. When I go to category (product listing) page, it works fine. But when I go to any product detail page, I get the following error:-

There has been an error processing your request

Exception printing is disabled by default for security reasons.

I don’t get the detailed information about the error as I used to get in previous versions of Magento.

Solution:

In your magento root, there is a folder called errors.

Go inside the errors folder.

There is a file named local.xml.sample.

Rename it to local.xml

Hence, the problem is solved. Now, I am able to see detailed error information.

Another Problem:

Now, when I try to open any product detail page, I get the following error.

Warning: Varien_Autoload::include(Mage\Catalog\Model\Resource\Eav\Mysql4\Product\Attribute\Backend\Tierprice.php) [varien-autoload.include]: failed to open stream: No such file or directory

If I try to add product to cart from product listing page, the product is not added to cart. And, I get the following error message:-

Cannot add item to shopping cart

Solution:

Tierprice.php is not present in app\code\core\Mage\Catalog\Model\Resource\Eav\Mysql4\Product\Attribute\Backend.

There is a file named Tierprice.php0000664.

Rename it to Tierprice.php. Hence, the problem is solved. Now, I am able to open product detail page. And, I am also able to add product to shopping cart.

Hope this helps. Thanks.