is set to "thinprint" incorrectly. You can often resolve this by following the VMware Knowledge Base Article 95329 or manually editing the file to ensure serial0.present = "FALSE" if you don't need the port [ For VMware ESXi/vSphere Users: Check Licensing:
If you’ve recently powered on a VMware Workstation or ESXi virtual machine only to be greeted by the warning message you aren’t alone. This is a common configuration hiccup that occurs when a VM is looking for a physical or virtual serial (COM) port that the host system can’t provide.
The VM might be configured to connect to a physical serial port (COM1, etc.) on the host that doesn't exist or is currently being used by another application.
If you are dealing with other connected devices showing similar errors, I can help. Could you tell me: virtual device serial0 will start disconnected
The VM configuration file ( .vmx ) may be instructed to map serial0 automatically to a physical COM port on the host machine. If the physical host laptop or desktop lacks a physical DB9 serial port, or if the port is disabled within the host machine’s BIOS/UEFI, initialization fails.
Troubleshooting VMware: "Virtual device serial0 will start disconnected"
For advanced users or situations where the VMware graphical user interface fails to apply the changes, you can resolve the issue by manually editing the virtual machine's configuration file ( .vmx ). is set to "thinprint" incorrectly
: VMs built from pre-packaged templates often include default virtual devices that the user does not actually need. The virtual machine tries to spin up everything listed in its file system, resulting in warnings for unused components. Step-by-Step Fixes to Resolve the Warning
Method 2: Manually Editing the .vmx File (Recommended for Fusion)
Within 30 seconds, both interfaces should transition to up/up . The original disconnected message is now a relic of the boot sequence. The VM might be configured to connect to
Choose "Use output file" to log serial data to a file.
Most modern operating systems (Windows 10/11, standard Linux distros) do not require a serial port to function. If you aren't doing low-level kernel debugging or connecting to industrial hardware, the easiest fix is to delete the device. the virtual machine. Right-click the VM and select Settings . Go to the Hardware tab. Locate Serial Port (or Serial0) in the list. Click Remove . Click OK and restart the VM. Method 2: Disconnect at Power On
The error occurs because the virtual machine's configuration file ( .vmx ) instructs VMware to connect a virtual serial port (COM port) to a physical or logical resource that is missing, busy, or inaccessible on your host machine. The most common triggers include: