Customers observed the following behavior:

• PVS target devices boot successfully in maintenance / read-write mode, but fail in read-only (Standard) mode.
• During boot:
• Windows shows “Getting devices ready”
• System reboots unexpectedly
• The process repeats → continuous boot loop
• Issue appears after applying Windows updates (e.g., KB patches) or updating templates
• Booting the same vDisk on the template/master VM works correctly

This issue is caused by a mismatch in VMware virtual hardware configuration between:

• The VM used to create or last boot the vDisk in read-write (Private) mode.
• The production PVS target devices

In particular:

• Different VMware virtualHW.version values between master/maintenance target VMs and  production target VMs
• Example:
• Master/maintenance target VM: higher hardware version (e.g., 13, 19)
• Production targets: lower hardware version (e.g., 10, 11)

Behavioral explanation

• After Windows updates, the OS may require hardware reconfiguration
• When booting on different virtual hardware:
• Windows detects a hardware mismatch
• Attempts to reconfigure devices and triggers a reboot
• In Standard (read-only) mode:
• Changes cannot be persisted
• Reconfiguration repeats on every boot
• Result:
• Continuous reboot loop

Standard PVS guidance is to ensure hardware configuration where a vDisk is last booted in read-write (Private) mode fully matches where it is later booted in read-only (Standard) mode.

Ensure identical virtual hardware configuration, in these scenarios identical VMware virtualHW.version, between:

• The master/maintenance targets where the vDisk is last booted in read-write (Private) mode.
• The production PVS target devices where the vDIsk is booted in read-only (Standard) mode.

Citrix Provisioning Services (PVS) target devices may fail to boot and enter a continuous reboot loop when booting vDisks in read-only (Standard) mode after Windows updates are applied. This is caused by a mismatch in VMware virtual hardware configuration between the system where the vDisk was last booted in read/write mode and the production target devices.