Magento 2: Invalid header value detected

Question

On opening a certain product page, we are getting the following error

"exception":"[object] (Zend\\Http\\Header\\Exception\\InvalidArgumentException(code: 0): Invalid header value detected at /app/6l7tzyfknugxk/vendor/zendframework/zend-http/src/Header/GenericHeader.php:53)"

We cannot find anything wrong in the product info in the admin.

Answer 1

Check the names of your products, maybe it contains special characters, or your header in the product contains some special characters.

Answer 2

It's easy to debug, and the reasons can be different.

Go to:

vendor/zendframework/zend-http/src/Header/GenericHeader.php:53

Add var_dump in this part:

if (! HeaderValue::isValid($parts[1])) {
    var_dump($parts[1]);
    throw new Exception\InvalidArgumentException('Invalid header value detected');
}

Check what exactly is not correct and fix it.

In my case, it was empty char at the end string of base_url