A: This suggests a persistent environment issue: a local security solution that resets the agent database on boot, or a Group Policy that overwrites your proxy settings. Run procmon to see what touches the agent.db file.
If the issue is related to communication, you may need to manually enable the correct cipher suites: Download the tool from Nartac Software .
For legacy systems, ensure all required Microsoft updates are installed. Specifically, the Microsoft KB3042058 update (which updates the default cipher suite priority order) is often mandatory for successful installation on Server 2008 R2.