FluxDeployDocs
Topics: ISO Library

ISO Library

The ISO Library stores uploaded Windows installation ISO files, which serve as source material for the WIM Customization wizard. ISOs must be uploaded here before you can create custom Windows images.

Uploading ISOs

Navigate to ISO Library and click Upload ISO:

  1. Click Choose File and select a Windows ISO (e.g., en-us_windows_11_24h2_x64.iso)
  2. Enter a descriptive name
  3. Click Upload - the file is streamed directly to the server

The maximum upload size for ISO files is 20 GB. Progress is reported in real time via JavaScript interop.

File Validation

Uploaded files are validated using magic byte checks:

  • ISO 9660 signature (CD001) is verified at the standard offsets
  • Extension verification ensures only .iso files are accepted
  • Files are streamed to a GUID-named temp file, validated, then renamed to the final path

Version Detection

After upload, the system probes the ISO to detect the Windows version it contains. This information is displayed in the library table. If detection fails initially, use the re-detect button in the row's action column to retry the probe.

The original uploaded filename is shown as the Name cell's tooltip rather than a column of its own, since for most uploads the two are the same text.

Storage Location

ISOs are stored in {ScratchBasePath}/ISOs/. The resolved path depends on your installation:

  • MSI install with data drive: {DataDrive}:\FluxDeploy-Data\Scratch\ISOs\
  • Default: Relative to the application directory

Usage in WIM Customization

The Create Windows Image wizard on the Windows Images page references ISOs from this library. When you select an ISO in the wizard:

  1. The ISO is mounted via PowerShell Mount-DiskImage
  2. DISM probes the install.wim (or install.esd) for available editions
  3. You select an edition, and the wizard copies the source WIM to a scratch directory for customization

Note: If no ISOs are uploaded, the Create Windows Image button redirects you to the ISO Library page first.

Deleting ISOs

Click Delete to remove an ISO. Deletion is blocked if the ISO is referenced by any active WIM customization jobs. The file is removed from both the database and disk.

Best Practices

  • Upload ISOs from Microsoft's Volume Licensing Service Center (VLSC) or Visual Studio subscriptions for clean, unmodified source media
  • Keep multiple versions available (e.g., Win11 23H2 and 24H2) to support different deployment scenarios
  • Delete old ISOs after creating all needed WIM images to reclaim disk space