This message typically appears in VMware Workstation VMware Fusion
when the software can't find or use the serial port assigned to the virtual machine. In recent updates (Fusion 13.5+ and Workstation 17.5+), this is most commonly caused by the removal of support for ThinPrint (virtual printing). Broadcom support portal Why this is happening Discontinued ThinPrint Support
: Newer versions of VMware no longer support the "ThinPrint" technology, which often used to handle virtual printing. Legacy Settings
: If your VM was created in an older version, it still has "Printer" enabled in its settings, but the hypervisor no longer knows how to connect it. How to fix it Option 1: The Easy Way (Settings Menu) Power off the virtual machine. Virtual Machine Settings (or right-click the VM > Settings). Select the device from the hardware list.
If you want to keep the device but stop the warning, uncheck Connect at power on Broadcom Community Option 2: The Manual Fix (Editing the .vmx file)
If the "Printer" device doesn't show up in the menu, you can manually remove the legacy lines from the VM's configuration file: completely. Navigate to the folder where your VM is stored and open the file with a text editor. Find and delete the following lines (if they exist): serial0.fileType = "thinprint" serial0.fileName = "thinprint" serial0.present = "TRUE" Save the file and restart your VM. Broadcom support portal virtual device
Parameter "serial0.fileType" has an invalid value "Thinprint
If you are a standard user running Windows or Linux desktops, simply removing the Serial Port from the settings is the permanent solution.
The error message "Virtual device serial0 will start disconnected" typically occurs in
environments and indicates that a virtual serial port cannot find its intended hardware or software backend during power-on
. This issue is most frequently tied to deprecated printing features or misconfigured virtual machine (VM) settings. Core Causes ThinPrint Deprecation : In recent versions like VMware Workstation 17.5 Fusion 13.5
, support for "ThinPrint" (a virtual printing technology) has been discontinued. VMs created in older versions often still have a serial port configured to use this driver, which now triggers the "invalid value" warning. Resource Conflicts
: The guest OS may be attempting to allocate the virtual device to a COM port that is already in use by the host system or another process. Licensing Restrictions
: In enterprise environments (ESXi), certain licenses do not permit the use of remote serial ports, causing the device to default to a disconnected state. Backend Connectivity
: If the serial port is configured to connect to a physical host port, a named pipe, or a specific file that is currently unavailable or inaccessible, the VM will power on with the device disconnected to prevent a full boot failure. Resolution Strategies Disable Virtual Printing : The most common fix is to navigate to Edit > Preferences > Devices in VMware Workstation and uncheck "Enable virtual printers" Modify VM Settings : Right-click the affected VM, go to , select the Serial Port device, and uncheck "Connect at power on"
. If the printer is not needed, you can remove the device entirely. Edit the .vmx File
: For users of VMware Fusion or advanced users, manually editing the VM configuration ( ) file to remove entries like serial0.fileType = "thinprint" can permanently resolve the error. Advanced vCenter Configuration
: For persistent network-backed serial port issues in vSphere, adding the parameter vpxd.SerialPort.PersistNetworkBacking = "True" virtual device serial0 will start disconnected
in the vCenter Server's advanced settings can help maintain connections. Impact on Operations In most cases, this message is a non-critical warning
. Unless your workflow specifically requires a serial console or virtual printing, you can typically dismiss the message and the VM will function normally. for editing the file on your specific operating system? Virtualization Architect Technical Support Engineer
When a virtual machine starts with the warning "Virtual device serial0 will start disconnected," it typically means the VM is trying to initialize a serial port that is either misconfigured, pointing to a non-existent physical resource, or linked to a legacy feature that is no longer supported. Core Causes of the Warning
ThinPrint Feature Removal: The most common reason in modern versions of VMware Workstation (17.5+) and VMware Fusion (13.5+) is the removal of the ThinPrint virtual printing feature. These newer versions no longer support the ThinPrint protocol, which often utilized serial0.
Missing Host Resources: The VM configuration might be set to map serial0 to a physical COM port on the host machine that is currently in use by another application or simply does not exist.
Disconnected on Power On: The "Connect at power on" option for the serial device may be unchecked in the VM settings, triggering a notification that it will remain inactive. How to Resolve the Warning
Depending on your needs, you can either remove the device entirely or reconfigure it to clear the error. Option 1: Remove the Printer Device (Recommended)
If you do not explicitly use virtual printing, removing the legacy device is the cleanest fix. Power off the virtual machine completely. Open Edit Virtual Machine Settings.
Select the Printer or Serial Port device associated with serial0. Click Remove and save the changes. Option 2: Edit the VMX Configuration File
For advanced users or situations where the GUI does not show the device (common in Fusion or Workstation updates), you can manually remove the entries from the .vmx file.
Locate your VM's folder and open the .vmx file with a text editor. Find and delete the following lines if they exist: serial0.fileType = "thinprint" serial0.fileName = "thinprint" serial0.present = "TRUE" Save the file and restart the VM. Option 3: Disable "Connect at Power On"
If you want to keep the device but stop the warning, you can tell VMware not to attempt a connection during boot.
In the VM settings, go to the Serial Port section and uncheck Connect at power on. This will stop the system from checking for the resource every time it starts. Why this happens with Printers
Legacy VMware versions automatically added a virtual printer that used a virtual serial port to communicate with host drivers. Because Broadcom/VMware discontinued ThinPrint, the software identifies a device it can no longer operate, resulting in the "start disconnected" status. AI responses may include mistakes. Learn more VMware Cannot Connect the Virtual Device sata0:1 Error
How to Fix: "Virtual device serial0 will start disconnected"
If you just powered on your VMware virtual machine and were greeted by the warning "Virtual device serial0 will start disconnected,"
you aren’t alone. While it sounds like a critical hardware failure, it is usually just a configuration "ghost" left behind by old software or missing physical ports. What Does This Error Actually Mean? This message typically appears in VMware Workstation VMware
The error indicates that your VM is configured to look for a serial (COM) port on your physical computer, but it can’t find one to "handshake" with. Because the VM can't establish this link, it simply starts with that specific virtual device disabled. Common Causes The "ThinPrint" Legacy:
Most modern occurrences are caused by a recent VMware update (Workstation 17.5+ or Fusion 13.5+). VMware discontinued support for
(a virtual printing technology), but many older VMs still have "Printer" devices in their settings that rely on Missing Physical Hardware:
You have a Serial Port added to your VM settings, but your actual laptop or desktop doesn't have a physical COM port. Conflict with Host Drivers:
If you are using a USB-to-Serial adapter, the host OS might not have the correct drivers (like CH340 or FTDI) installed, making the port "invisible" to the VM. How to Fix It Method 1: The Quick GUI Fix (Recommended)
The easiest way to stop this message is to remove the device that is trying to use the serial port. the virtual machine. VM > Settings (or right-click the VM and select
in the hardware list. If you don't need to print from your VM, select it and click If there is a Serial Port listed that you don't use, select it and click and restart the VM. Method 2: The .vmx File Surgery
If the GUI doesn't work or you are on an encrypted VM, you can manually "clean" the configuration file.
Navigate to your VM's folder on your hard drive and locate the Open it with a text editor like Search for lines starting with If you see serial0.fileType = "thinprint" , you can safely delete all lines or change serial0.present the file and try powering on again. Method 3: Fixing Real Serial Connections If you actually
the serial port for a project (like Arduino or industrial hardware): Check Host Drivers: Ensure your host machine recognizes the device in Device Manager (Windows) or ls /dev/tty* Update Connection Mapping:
In VM Settings, ensure the "Connection" is set to the correct physical port (e.g., /dev/ttyUSB0 In 90% of cases, this error is just
complaining that it's been retired. Deleting the "Printer" hardware from your VM settings is the fastest way to get a clean, error-free boot. specific platform like LinkedIn or a technical documentation site?
Parameter "serial0.fileType" has an invalid value "Thinprint 10 Nov 2023 —
If you're seeing the error "Virtual device serial0 will start disconnected" when powering on a VMware virtual machine, you aren't alone. This message typically appears because of a recent change in how VMware handles printing, specifically the removal of ThinPrint support in newer versions like VMware Workstation 17.5 and Fusion 13.5. Here is how to fix it based on your setup. Option 1: The Quick Fix (Recommended)
The easiest way to resolve this is to remove the legacy printer device that is causing the conflict. Shut down your virtual machine completely. Open the Virtual Machine Settings. Find Printer in the list of hardware devices. Select it and click Remove. Click OK and restart the VM. Option 2: For VMware Workstation Users
If you want to disable the feature globally to prevent this on other VMs: Go to Edit > Preferences. Navigate to the Devices tab. Uncheck the box for "Enable virtual printers". Option 3: Manual Edit (Advanced)
If the "Printer" device doesn't show up in your settings or you are using VMware Fusion, you can manually edit the configuration file: Close VMware and find your VM's .vmx file on your computer. The Message: VMware cannot find the physical connection
Open the .vmx file with a text editor (like Notepad or TextEdit). Search for and delete these lines: serial0.present = "TRUE" serial0.fileType = "thinprint" serial0.fileName = "thinprint" Save the file and start your VM. Why is this happening?
Starting with VMware Fusion 13.5 and Workstation 17.5, VMware officially retired ThinPrint, a legacy technology that mapped printers via a virtual serial port (serial0). Because the software no longer supports the "thinprint" file type, it flags it as an invalid value and tells you the device will start disconnected.
Does your virtual machine have encryption or a TPM enabled? These can sometimes complicate the manual editing process.
The error message "Virtual device serial0 will start disconnected" in VMware (Workstation or Fusion) most commonly occurs because support for ThinPrint (virtual printing) has been discontinued in recent versions like Workstation 17.5 and Fusion 13.5. Primary Fixes Remove the Printer Device (Easiest Method): Shut down the virtual machine. Go to VM Settings > Hardware tab. Select the Printer device and click Remove. Click OK and restart the VM.
Edit the .vmx Configuration File (Advanced):If the device isn't visible in the GUI or the message persists, you can manually remove the offending lines from your VM's configuration file: Open your VM's folder and locate the .vmx file. Open it with a text editor (like Notepad or TextEdit). Find and delete the following lines: serial0.fileType = "thinprint" serial0.fileName = "thinprint" serial0.present = "TRUE" Save and close the file, then restart your VM. Troubleshooting Physical Port Conflicts
If you actually need to use a serial port and the error says "no corresponding device available on the host," try these steps:
Verify Host COM Port: Ensure the serial port (e.g., COM1 or /dev/ttyS0) is enabled in your host's BIOS and is not being used by another application (like Putty).
Manual Mapping: Manually edit the .vmx file to point to the correct host port by changing the serial0.fileName to the specific port name, such as COM3 on Windows or /dev/tty.USA19H3d2P1.1 on Mac.
For more detailed guides, you can visit the Broadcom/VMware Knowledge Base or the VMware Fusion community discussions. If you’d like, let me know:
Which VMware product and version you are using (e.g., Workstation 17.5)?
Do you actually need to use a serial device (like a console cable), or do you just want the error to go away? I can provide the exact steps for your specific version. USB Serial Port kinda working | Fusion - Broadcom Community
This message typically appears in virtual machine platforms (like VMware, VirtualBox, or QEMU) or network simulation tools (like GNS3 or EVE-NG).
This message occurs when a Virtual Machine is configured to use a Serial Port (Serial0), but the hypervisor cannot establish the connection at boot time. Common causes include:
serial.out), but that file has not been created on the host OS yet.If you unchecked "Connect at power on" but still get the message:
serial1, serial2, etc., and remove them too.prefs.ini file in your VMware installation folder or your user documents folder (%AppData%\VMware on Windows). Sometimes global preferences force a connection.You likely accidentally added a Serial Port during the setup wizard.
Q: Does this warning affect clone or snapshot operations?
A: No. Snapshots and clones remain unaffected. The disconnected serial port does not hold any state.
Q: Can I hide the warning without removing the serial port?
A: In VMware Workstation, you cannot suppress warnings globally. The only way is to connect the port to a valid target (file or pipe) or remove it.
Q: Does this appear in VirtualBox or Hyper-V?
A: VirtualBox calls it "Serial Port 1 – disconnected" and Hyper-V shows no explicit warning unless you open guest settings. The behavior is VMware-specific in phrasing but functionally similar.
Q: What if I have multiple serial ports (serial1, serial2)?
A: The same rule applies. Each disconnected port will log a separate warning.