# Links to VMWare to Proxmox Migration Moving the Altiris server VM from VMware to Proxmox means the same Windows server was moved to a different virtualization platform, and that can change virtual NICs, MAC addresses, network paths, VLAN behavior, firewall behavior, IIS auth behavior, or service account behavior even if the VM “looks” like the same server from the inside. Why it fits Your logs show a very specific pattern: the agent can still establish and authenticate its main persistent connection to the NS over HTTPS, but Task Server registration then fails with “Task Server activities are paused” over HTTPS and falls back to HTTP, where it gets 401 Unauthorized / logon failure. Broadcom’s Altiris guidance says 401 errors on Altiris/ClientTaskServer/Register.aspx are tied to IIS authentication configuration, anonymous access handling, IUSR rights, or a locked Agent Connectivity Credential. Your logs show a very specific pattern: the agent can still establish and authenticate its main persistent connection to the NS over HTTPS, but Task Server registration then fails with “Task Server activities are paused” over HTTPS and falls back to HTTP, where it gets 401 Unauthorized / logon failure. Broadcom’s Altiris guidance says 401 errors on Altiris/ClientTaskServer/Register.aspx are tied to IIS authentication configuration, anonymous access handling, IUSR rights, or a locked Agent Connectivity Credential. Most likely link The strongest clue is the HTTP 401 on the Task Server registration page. Broadcom says that exact Altiris symptom usually points to IIS auth settings, anonymous auth behavior, user-rights issues for IUSR, or Agent Connectivity Account lockout. A platform migration could trigger that indirectly if the server picked up different security policy application, different IIS behavior, changed service identities, broken domain trust timing, or altered network/security controls after the move. Your first log also shows “computer not known to server” and policy/GUID reset behavior, which can happen when the server-side relationship gets disrupted. Altiris documentation notes the platform relies on machine identity and GUID relationships, so server-side changes can surface as re-registration behavior. What to check first Ask your infrastructure team to verify these items on the Altiris server after the migration: IIS settings for Altiris/ClientTaskServer and TaskManagement, especially authentication configuration. Whether the Agent Connectivity Account is locked out or whether IUSR lost “Allow log on locally.” Whether any firewall, VLAN, proxy, or network ACL behavior changed during the move. Broadcom notes Altiris communication failures can come from firewall, proxy, or VLAN misconfiguration. Whether the VM’s virtual NIC type, MAC, or guest integration tools changed during the VMware-to-Proxmox migration. Migration guidance specifically flags those as common gotchas.