> For the complete documentation index, see [llms.txt](https://guide.prismlive.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://guide.prismlive.com/desktop/guides/error-solution/error-information/dual-output-error-solution-guide.md).
# Dual Output – Error Solution Guide
Windows, Mac
### Overview
PRISM Live Studio provides a **Dual Output** feature that allows you to stream both **horizontal** and **vertical** broadcasts simultaneously.\
This feature lets creators deliver content optimized for both PC and mobile viewers at the same time.
However, some users have encountered the following error message:
This error occurs when Dual Output is enabled, but **only one of the two outputs** — either **Horizontal Output** or **Vertical Output** — has a connected channel.
### Cause
When using the Dual Output feature, you must connect **at least two channels**, and both output directions must have assigned channels.
To summarize:
1. At least **two streaming channels** must be connected.
2. Both **Horizontal Output** and **Vertical Output** must have their respective channels assigned.
***
### Solution
#### CASE 1. Only one channel is linked while Dual Output is enabled
**Problem**
You are trying to use Dual Output, but only **one channel** has been connected.
**Solution**
1. Click the **three-dot menu (⋮)** next to **My Channel**.
2. Select **Add Channels** to connect an additional channel.
* At least two channels must be connected to use Dual Output.
3. After adding the channel, make sure both **Horizontal Output** and **Vertical Output** are properly assigned.
4. Click **Go Live** to begin your broadcast.
***
#### CASE 2. Multiple channels are linked, but only one output is assigned
**Problem**
Dual Output is enabled and more than one channel is connected,\
but only one output (e.g., **Horizontal Output**) has been configured — while the other (**Vertical Output**) remains empty.
**Solution**
1. Hover over a channel and click the **Dual Output icon (PC + Mobile icon)**.
2. Select the unassigned output (e.g., **Vertical Output**) to assign a channel.
3. Verify that both **Horizontal Output** and **Vertical Output** have connected channels.
4. Click **Go Live** to begin your broadcast.
---
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