# \[FAQ\] Custom URL protocol links with target="\_blank" don't open in io.Connect Desktop

**URL:** https://community.interop.io/t/faq-custom-url-protocol-links-with-target-blank-dont-open-in-io-connect-desktop/651
**Category:** io.Connect Desktop
**Tags:** FAQs
**Created:** [August 11, 2026, 9:19am UTC](https://community.interop.io/t/faq-custom-url-protocol-links-with-target-blank-dont-open-in-io-connect-desktop/651 "2026-08-11T09:19:50Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![toni.petrov](https://yyz2.discourse-cdn.com/flex028/user_avatar/community.interop.io/toni.petrov/32/17_2.png) [@toni.petrov](https://community.interop.io/u/toni.petrov)
#### Post date: [August 11, 2026, 9:19am UTC](https://community.interop.io/t/faq-custom-url-protocol-links-with-target-blank-dont-open-in-io-connect-desktop/651/1 "2026-08-11T09:19:50Z")

</div>

## Problem

A custom URL protocol is registered on the machine through a `.reg` file. Clicking anchor links that use the `target="_blank"` attribute does nothing after upgrading to 9.9. Removing `target="_blank"` from the anchor makes the links work.

## Cause

When a custom-protocol link uses `target="_blank"`, io.Connect Desktop applies a security check while handling the request to open a new window. If the custom protocol is not declared in the io.Connect Desktop protocol-handler configuration, the request is blocked as a non-HTTP/file protocol. As a result, the link is blocked and the registered protocol is not executed. This can be vonfirmed in the logs:

​` [INFO] wnd ... - the "my-custom-protocol://..." is non-http/file protocol and is NOT allowed to be opened.`

## Solution

Аdd your protocol handler in the system.json with the `"register"` property to `false` when the protocol is already registered by another mechanism (such as a `.reg` file) and io.Connect Desktop will be familiar with it.

```auto
"protocolHandler": [
     {
        "enabled": true,
        "type":"custom",
        "allowOpeningURLs": true,
        "protocol": "my-custom-protocol",
        "register": false,
        "startNewInstance": {
            "enabled": true
        }
      }

```