> For the complete documentation index, see [llms.txt](https://quicly.gitbook.io/help/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://quicly.gitbook.io/help/faq/common-errors-and-fixes.md).
# Common Errors & Fixes
## **Navigating Common URL Conversion Errors**
During the URL shortening process, certain issues may arise, leading to error messages. Below, we've outlined common errors and provided explanations to help you troubleshoot and resolve these issues efficiently
img 1 - Common errors in url conversion
### **1. Long URL Issues:**
Errors associated with the long URL may occur due to various reasons:
* **Missing Protocol**: Ensure the URL begins with ‘http\://’ or ‘https\://’.
* **Prohibited Content**: The link must not include blacklisted domain keywords associated with explicit content, gambling, or substances (e.g., sex, gambling, porn, xxx, drugs, alcohol, cannabis).
* **Invalid Domain Ending**: The domain must conclude with a valid ending, such as '.com' or '.net'.
* **Invalid Characters**: Ensure the URL does not contain any invalid or unsupported characters.
### **2. Alias Errors:**
The custom alias field also has specific requirements:
* **No Spaces Allowed**: Ensure there are no spaces within the alias.
* **Character Restrictions**: Use only alphanumeric characters (0-9, a-z, A-Z), hyphens (-), or underscores (\_).
* **Character Limit**: The alias must be between 7 and 20 characters in length.
* **Unique Alias**: The alias must not be already in use.
### **3. UTM Builder Notes:**
While UTM parameters are optional, if you choose to provide one of the main parameters (utm\_campaign, utm\_source, or utm\_medium), all other main parameters are required for a comprehensive tracking setup. The ‘utm\_term’ and ‘utm\_content’ parameters remain optional.