: The most frequent cause in VMware is tied to the "Virtual Printing" feature. This feature is disabled by default on Windows hosts. When a virtual machine is configured to use this feature (common in VMs created with older versions of VMware), but the global setting is off, VMware generates the serial0 warning. The VM is essentially looking for a virtual printer, and when it doesn't find it, it disconnects the port assigned to it. This is precisely why a KB article states the message is a "warning for a configuration for Thinprinting feature".
No. Many pre-built Linux appliances include a virtual serial port for legacy console access. The message is cosmetic. : The most frequent cause in VMware is
By internalizing this behavior, you stop fighting the emulator and start learning the networking. And after all, the goal of a virtual lab is to emulate the real world—where unplugged cables mean disconnected circuits. The VM is essentially looking for a virtual
This is the simplest and most common fix for Workstation and Fusion.
If the virtual serial port is required for your workflow, you must fix its underlying connection path. Navigate to the menu of the powered-off VM.
In the vast majority of cases, the answer is . The consensus across many community posts and support forums is that this message is informational and can be safely ignored if you are not using the serial port.