how to display recently viewed products on homepage in magento 1.9.3.3

Question

{{block type="reports/product_viewed" template="reports/product_viewed.phtml"}}

<?php if ($_products = $this->getRecentlyViewedProducts()): ?>
<div class="block block-list block-viewed">
    <div class="block-title">
        <strong><span><?php echo $this->__('Recently Viewed Products') ?></span></strong>
    </div>
    <div class="block-content">
        <ol id="recently-viewed-items" class="mini-products-list">
        <?php foreach ($_products as $_item): ?>
            <li class="item">
                <a href="<?php echo $this->getProductUrl($_item) ?>">
                    <span class="product-image"><img src="<?php echo $this->helper('catalog/image')->init($_item, 'thumbnail')->resize(50, 50)->setWatermarkSize('30x10'); ?>" width="50" height="50" alt="<?php echo $this->escapeHtml($this->getProductName()) ?>" /></span>
                </a>
                <div class="product-details">
                    <p class="product-name">
                        <a href="<?php echo $this->getProductUrl($_item) ?>">
                            <?php echo $this->helper('catalog/output')->productAttribute($_item, $_item->getName() , 'name') ?>
                        </a>
                    </p>
                </div>
            </li>
        <?php endforeach; ?>
        </ol>
        <script type="text/javascript">decorateList('recently-viewed-items');</script>
    </div>
</div>
<?php endif; ?> 

Answer 1

Make sure your block is whitelisted

You can make block whitelisted from your admin panel in System > Permission > Blocks

Add new entry if not present say for example reports/product_viewed and set is Allowed to yes.

With the inclusion of the security patch SUPEE-6788 blocks used in CMS pages and emails must be whitelisted.