When Avast UI failed to load appears, or the app reports that the AV service is not responding, the antivirus engine is still installed but its background service is not running or cannot talk to the interface. Your computer usually stays protected, but you cannot open settings or run a scan. The fixes below start with the quickest and work up to a clean reinstall; most people are sorted by step three.
Fix 1: restart the Avast service
- Press Windows+R, type services.msc and press Enter.
- Find Avast Antivirus in the list.
- Right-click it and choose Restart. If it is stopped, choose Start.
- Double-click it, set Startup type to Automatic, then click OK and open Avast again.
Fix 2: switch on Remote Desktop Services
This is the fix that surprises people. The Avast interface depends on a Windows component called Remote Desktop Services, even if you never use remote desktop. If that service is disabled, for example by a “speed up Windows” tweak or a tuning tool, the interface cannot start.
- Open services.msc again.
- Find Remote Desktop Services, double-click it and set Startup type to Manual (or Automatic).
- Click Start, then OK, and restart the computer.
Fix 3: repair the installation
- Open Settings > Apps > Installed apps.
- Find Avast, click the three dots and choose Modify (or Uninstall, then Change in older versions).
- Choose Repair and let it finish, then restart the computer.
Fix 4: update or reinstall
If the error survives a repair, install the latest version over the top from Avast’s website; a newer build often fixes interface problems after a Windows update. If that fails, use Avast’s own removal tool to uninstall cleanly, restart, and install again. Reinstalling keeps your licence, but note it down first so you can sign back in.
What causes the error?
| Cause | Sign | Fix |
|---|---|---|
| Avast service stopped | Service shows “Stopped” in services.msc | Fix 1 |
| Remote Desktop Services disabled | Error returns after every restart | Fix 2 |
| Damaged program files | Error after a crash or power cut | Fix 3 |
| Conflict with another antivirus | Started after installing other security software | Remove the other product, then Fix 3 |
| Old version after a Windows update | Started right after an update | Fix 4 |
Am I protected while the interface is broken?
Usually yes, because the scanning service can run even when the window will not open, but you cannot be sure and you cannot change settings. Until it is fixed, make sure Windows Security is switched on so you are not left without protection, and avoid downloading unfamiliar files.
Frequently asked questions
Does this affect Avast Free and paid versions?
Yes, both, and the same steps apply to AVG, which uses the same engine.
The error appears every time Windows starts. Why?
That pattern points to Fix 2: a service the interface depends on is set to Disabled, so it never starts with Windows. Set Remote Desktop Services to Manual or Automatic and the message should stop coming back.
Will I lose my settings?
A repair keeps them. A clean reinstall resets them, so note any exclusions you have added before removing the program.
Should I just switch to Windows Security?
It is a reasonable option: Windows Security is built in and needs no extra software. Uninstall Avast fully first, since two antivirus products can conflict.
In most cases “Avast UI failed to load” is fixed by restarting the Avast service and making sure Remote Desktop Services is allowed to run. Work down the list in order and you will get the interface back without losing your licence. If none of the four steps helps, note the exact error text and check Avast’s support pages for your version, since some builds have their own known issues.