Windows server installation issue on proxmox 9.0

[Mohammad lukman]

Does anyone have a solution for installing Windows Server 2025/2022 on Proxmox 9.0 PVE? I created a VM with 8 processor cores and 16 GB RAM, then uploaded the Windows Server 2025 ISO. When I try to start the installation, the ISO does not boot and shows the message “Boot device not found.” However, other OS ISO images like Windows 10 and Ubuntu boot and install successfully. Why is Windows Server 2025 ISO not supporting on Proxmox 9.0, while it works on Proxmox 7.4?

I have another question: when I try to create a bootable pen drive using the Proxmox 8.4 ISO, it does not become a successfully bootable USB. Is there any other method to do this?

Please help ME

 

[_gabriel]

There is a bug in the upload from WebUI

B

[SOLVED] Thread 'Proxmox VE 9.0 ISO Upload Corrupts Some Windows Server 2025 ISOs'

Aug 10, 2025

I've recently done a fresh install of Proxmox VE 9.0 and came across this issue while trying to upload ISOs for a Windows Server 2025 VM. When I try to upload either SW_DVD9_Win_Server_STD_CORE_2025_24H2.4_64Bit_English_DC_STD_MLF_X23-96921.ISO or SW_DVD9_Win_Server_STD_CORE_2025_24H2.9_64Bit_English_DC_STD_MLF_X24-08243.ISO, the resulting ISO that ends up in /var/lib/vz/template/iso is about 3 GB larger than the original ISO, no longer matches the SHA256 checksum of the original ISO, and attempting to boot from it shows a "Boot Configuration Data" error screen. The oldest Windows Server...

• brendanw36
• iso upload windows server 2025
• Replies: 11
• Forum: Proxmox VE: Installation and configuration

 

[cwt]

This is not only related to the WebUI. I usually deposit ISOs on a NFS share. Since the latest PVE updates some (not all of them) ISOs produce this error when I try to setup Win VMs (11/2022/2025). The boot process ends up in the vBIOS setup. When I switch the ISO to an another version (for example: I have 4 different ISOs for W11 IoT LTSC) the boot process starts normally.