Step-by-Step: Create a Custom Windows ISO with CCleaner nLite Addon
Notes before you begin
- Compatibility: This guide assumes you’re customizing a Windows 7/8/XP-era ISO with nLite (or similar for later versions like vLite/NTLite). nLite works best with older Windows installers; for modern Windows ⁄11 use NTLite.
- Licensing & legality: Only customize ISOs for versions you legally own. Do not distribute Microsoft installation media unlawfully.
- Backups: Work on copies of ISOs and configuration files — keep originals untouched.
- Date: February 5, 2026.
Required tools and files
- Windows installation ISO (original, legal copy)
- nLite (or NTLite for newer Windows) installed on your PC
- CCleaner nLite Addon package (addon files compatible with your nLite/Windows version)
- A small tool to mount/extract ISOs (7-Zip, WinRAR, or Windows built-in ISO mounting)
- Optional: ISO rebuilding tool (ImgBurn or built-in nLite/NTLite ISO writer)
Step 1 — Prepare working folders
- Create a workspace, e.g., C:\ISO_Work</li>
- Extract the original Windows ISO contents into C:\ISO_Work\WinSource\ (mount ISO and copy all files or extract with 7-Zip).
- Place your nLite installation and the CCleaner addon files in C:\ISO_Work\Tools.
Step 2 — Verify addon compatibility
- Confirm the CCleaner nLite Addon version matches the Windows edition and nLite/NTLite version.
- If the addon provides an INF or script, open it in a text editor to check referenced file names and paths match those in WinSource. Adjust if needed.
Step 3 — Add CCleaner files to the source
- Locate where the addon expects CCleaner binaries and support files (commonly a folder like \(OEM\)\\(1\Program Files\CCleaner or a setup script).</li> <li>Create corresponding folders inside WinSource (e.g., WinSource\\)OEM\(\\)1\Program Files\CCleaner).
- Copy CCleaner executable(s), DLLs, and any license/INI files into that folder.
- If the addon includes an installer executable, place it in WinSource\Setup\ or the folder specified by the addon instructions.
Step 4 — Integrate addon scripts and registry tweaks
- If the addon includes .REG files or post-install scripts, put them where the Windows setup will run them (commonly WinSource\I386\\(OEM\) for older setups or in the \(OEM\) folder for automated runs).
- For unattended installs, add commands to the WinSource\I386\winnt.sif (or equivalent unattended answer file) to run the addon installer during first boot or GUI-runonce. Example entry for winnt.sif (older Windows):
- Under [GuiRunOnce] add a line to execute the installer.
- For NTLite, use its “Post-Setup/RunOnce” integration to add the addon installer and any command-line silent switches (e.g., /S for CCleaner).
Step 5 — Configure silent install (recommended)
- Check the CCleaner installer command-line switches for silent installation (commonly /S or /VERYSILENT).
- Test the silent install on a live machine or VM with the same OS version to ensure no prompts.
- Place the exact command into your unattended script or NTLite post-setup action, e.g.:
C:\Program Files\CCleaner\CCleaner.exe /S
Step 6 — Include registry and preferences
- If you want CCleaner defaults (rules, excluded files, scheduled tasks), export those registry keys and preference files from a configured machine.
- Add the REG files to the setup run sequence and import them (regedit /s Settings.reg) as part of the post-setup actions.
- If CCleaner uses an INI or settings file, copy it into the Program Files\CCleaner folder before building the ISO.
Step 7 — Use nLite/NTLite to finalize integration
- Launch nLite/NTLite and point it to C:\ISO_Work\WinSource\ as the source.
- Follow steps to integrate addons, drivers, updates, and post-install tasks. Use the “Add” or “Post-setup” features to include the CCleaner installer and any scripts.
- Configure unattended options, product key, user accounts, regional settings as desired.
- Let nLite/NTLite apply changes and optionally create a bootable ISO.
Step 8 — Build and burn/export ISO
- When nLite/NTLite finishes, use its built-in ISO creation or an external tool like ImgBurn to create a bootable ISO from the modified WinSource folder.
- Verify bootability by mounting the ISO or testing it in a virtual machine (VirtualBox, VMware).
Step 9 — Test the custom ISO
- Boot a VM with the new ISO and perform a full install using the unattended options you set.
- After installation completes, confirm CCleaner is installed, runs silently, and that preferences/registry settings applied correctly.
- Fix any path, timing, or permission issues by adjusting scripts or installer switches and rebuild.
Troubleshooting tips
- Installer not running: ensure correct paths in winnt.sif or RunOnce entries; use absolute paths.
- Silent install fails: test installer manually with the same switches; some installers need extra parameters (e.g., /NORESTART).
- Registry imports fail: run imports after administrative privileges are established (post-setup phase).
- Missing files on install: confirm all addon files were copied into the ISO source and referenced correctly.
Security and maintenance notes
- Keep CCleaner installer from official sources to avoid tampered binaries.
- Update the addon and CCleaner before rebuilding ISOs periodically.
- For network deployments, consider using enterprise deployment tools (SCCM, Intune) instead of custom ISOs.
Quick checklist
This procedure produces a bootable custom Windows ISO that installs CCleaner automatically during setup. Adjust paths and methods if using newer tools (NTLite) or newer Windows versions.