- Synapse X is a free tool and an upgraded version of the Synapse Lua script injecting software, specifically used to modify the Roblox games.
- The Synapse X UI download error primarily occurs due to security issues caused by your system.
- In this context, your system prevents downloading files that it suspects can be potentially harmful.
Roblox fans tend to modify certain features of a game using Synapse X, but the software sometimes fails to download the UI files as you try to launch/install the Synapse application.
While the error may appear due to the antivirus/firewall applications, it may also show up if the Synapse X software is not launched with administrative privileges.
If you come across the Check your virus protection error on Windows 10/11 notification, you can read our detailed guide to get rid of it.
This post will highlight a few solutions that may fix the Failed to download UI files. Please check your anti-virus software error.
But before that, we will see how to add an exception for Synapse X in the firewall settings.
How do I allow Synapse X through the firewall?
The Antivirus and the Firewall apps can also create conflict when you try to open or use the Synapse X software.
This can trigger the error failed to download launcher files. Please check your network firewall and av.
In such a case, you can turn off the firewall temporarily as shown below:
- Press the Win + R shortcut keys to open the Run console.
- Type Firewall.cpl in the search bar and hit Enter.
- It will open the Windows Defender Firewall window in the Control Panel.
- Here, click on Turn Windows Defender Firewall on or off on the left.
- Now, select the Turn off Windows Defender Firewall option for both Private and Public network settings.
- Press OK to save the changes.
Now, let’s proceed with the troubleshooting process for the failed to download the UI file error, but before that, make sure the Synapse X website is up and running.
How do I fix Synapse X failed to download bootstrapper files?
1. Disable the real-time protection and add an exclusion
- Click on the Windows Security icon in the system tray.
- As the Windows Security app opens, click on Virus & threat protection on the right.
- Next, go to Virus & threat protection settings and click on Manage settings.
- On the next screen, go to Real-time protection and turn it off.
- Now, scroll down, and under Exclusions, click on the Add or remove exclusion link.
- On the Exclusions page, click on Add an exclusion and select Folder.
- Now, look for Synapse X and select it to add an exclusion for it.
You can try launching Synapse X and it should be working now.
But, if you are using a third-party security solution, make sure you turn it off temporarily or add Synapse X as a trusted item (add to the exclusion list).
2. Open Synapse X with administrator rights
Now that the Synapse X software has the right to access the protected system resources, the failed to verify UI data Synapse X error should be fixed.
3. Use a VPN client
Sometimes, you may encounter the Synapse X download error, if your ISP blocks a crucial related file or process. Hence, using a VPN may help you deal with the error.
A practical solution to avoid connection errors with the Synapse X tool is to use a flexible VPN like PIA (Private Internet Access)
You have open-source VPN support and thousands of servers in many regions, a no-log policy, or advanced features like the network kill switch.
⇒ Get PIA
4. Turn off xFi advanced security
- Open the xFi advanced security app and click on More.
- On the next screen click on My Services.
- Now click on Disable to turn off xFi Advanced Security.
You can now try launching the Synapse X engine and the xFi Advanced Security by Xfinity will not block the access to the Synapse website anymore.
5. Try another network
The Synapse X app may sometimes fail to work due to a problem with the network connectivity.
In this case, you can try changing to a different network, or use your mobile phone internet through the mobile hotspot.
Synapse X is stuck on downloading DLLs
If the Synapse X is stuck on downloading DLLs for hours, in addition to the above methods, you can also delete the Synapse X /bin/ folder and turn off the auto-launch.
You can then run Synapse X as an administrator, and the error will not show up again.
Alternatively, you can clean boot your system before redownloading and reinstalling the Synapse X software or end any irrelevant processes through the Task Manager.
Besides, try to use the File Explorer instead of a file archiver utility to extract the Synapse archive.
Moreover, if you want to know how to download & use Synapse X for Roblox, we have another detailed guide for your reference.
If you are still struggling to use the Synapse X engine, you can leave your comments here in the comments box below.