The 'Another instance is running' error on Windows can prevent users from launching applications and is often caused by a background process already running.
To fix this error, you can start by removing Ad-Aware Web Companion from the Control Panel if it's causing the issue.
Check and close any running processes related to the software triggering the error message in the Task Manager.
If the error persists, a simple restart of the computer may resolve it, as restarting can often fix many Windows errors.
Reinstalling the problematic software can also help in resolving the 'Another instance is running' error message.
Creating a new Windows user account or performing a Clean Boot can help rule out conflicts causing the error.
Running the SFC/DISM commands via Command Prompt can help repair corrupted system files triggering the error.
Downloading and installing all pending Windows updates is recommended to fix the error caused by software bugs or glitches.
Following these methods can effectively address the 'Another instance is running' error message on Windows systems.
For further solutions or insights on fixing this error message, users can explore additional methods and contribute ideas in the comments section.