Install Magento 1.5 in localhost [wamp or xampp]

Step:1
Open \app\design\install\default\default\template\install\config.phtml

Step:2
Find the word in above file"config[unsecure_base_url]"

Step:3
Remove the class ‘validate-url’ from the input and then save the file
<li>
<label for="base_url"><?php echo $this->__('Base URL') ?> <span class="required">*</span></label><br />
<input type="text" name="config[unsecure_base_url]" id="base_url" value="<?php echo $this->getFormData()->getUnsecureBaseUrl() ?>"
title="<?php echo $this->__('Base URL') ?>" class="required-entry validate-url input-text" />
</li>

Step:4
<li>
<label for="base_url"><?php echo $this->__('Base URL') ?> <span class="required">*</span></label><br />
<input type="text" name="config[unsecure_base_url]" id="base_url" value="<?php echo $this->getFormData()->getUnsecureBaseUrl() ?>"
title="<?php echo $this->__('Base URL') ?>" class="required-entry input-text" />
</li>
Continue the installation.