Please be aware that you will need port information for step 3. These are the ports you need for Rainbow Six: Siege:
Here is the list of steps you can try:
1. Reset network hardware
2. Software conflicts
3. Port forwarding
4. Hosts file
5. Flush DNS
6. External restrictions
For more information about the in-game connectivity icons, please check out this article.
If you continue to have trouble after trying these steps, please feel free to contact us!