Battle.net:
- Open Battle.net > Click on Modern Warfare II.
- Select the Cog Wheel icon next to the Play button.
- Now, select Scan and Repair > Wait for the repair to complete.
Steam:
- Open Steam > Go to Library.
- Right-click on Modern Warfare II in your library.
- Go to Settings and select Properties.
- Click on Local Files and select Verify integrity of game files.
- Wait for the process to complete.
5. Check Your Internet Connection
You can also check the internet connection at your end whether it’s working fine or not. A slow or unstable network connectivity can trigger several issues with the matchmaking or server connectivity. In some cases, too many devices are connected to the same network which can also reduce the data speed. If you’re using Wi-Fi, try using an ethernet connection for better stability. Otherwise, try using a different connection instead.
6. Power Cycle the Wi-Fi Router
We’ll also recommend you perform a power cycle to your Wi-Fi router by following the steps below to easily clear networking glitches or temporary cache issues.
- Just Power Off the Wi-Fi router.
- Once the LED indicator stops blinking, unplug the power cable from the power source.
- Now, wait for around 30 seconds, and then plug back the power cable in.
- Then Power On the router and check for the issue again.
7. Disable Windows Firewall
Windows Firewall basically prevents unauthorized ongoing connections from the PC to online servers. You can try turning it off temporarily to check for the issue again.
- Open the Start Menu > Type Windows Firewall and click on Windows Defender Firewall from the search result.

- Now, click on Turn Windows Defender Firewall on or off from the left pane.

- Make sure to turn off all the Private, Domain, and Public Network Settings options.
- Finally, click on OK to save changes.
8. Temporarily Turn Off Antivirus
You can also try turning off the Windows Defender antivirus protection on your PC to ensure there is no antivirus software blocking the game files from running properly.
- Press the Win+I keys to open Windows Settings.
- Click on Update & Security > Click on Windows Security from the left pane.
- Now, click on the Open Windows Security button.
- Go to Virus & Threat Protection > Click on Manage Settings.
- Next, you’ll need to Turn Off the Real-time Protection toggle.
- If prompted, click on Yes to proceed further.
In case, you’re using any other third-party antivirus program on your PC then just turn off the real-time protection feature.
9. Check the Activision Online Services
Last but not least, make sure to check for Activision Online Services here to ensure there is an issue with the server downtime or outage. Sometimes the server unavailability or downtime can trigger several issues for the players. If the online status seems active or operational for all platforms then nothing to worry about. Keep retrying at your end. But if the online status seems problematic then wait for a couple of hours and try again. Visit the page and select Call of Duty: Modern Warfare II from the drop-down menu.
In conclusion, while encountering the MW2 Error Code 14515 can be frustrating for players eager to dive into the game, it’s essential to understand that such issues, especially within the Call of Duty franchise, are not uncommon. The current indications suggest a server-side bottleneck during high-traffic periods. Patience is key; waiting for off-peak hours may offer a smoother gaming experience. That’s it, guys. We assume this guide was helpful to you. For further queries, you can comment below.