There are 5 switches in total which we can use with the Type 1 Hotfixes (the other switches documented by Microsoft's Knowledge Base articles are irrelevant). Below you can find an explanation of them, and choose which ones you can use.

/U - Unattended Mode. No user interaction is required to install a hotfix, but you will see progress bar windows.

/Q - Quiet Mode. This functions exactly the same way as /U, but does not display any progress bar windows. You do not need to use /Q and /U together.

/O - Overwrites OEM Files without prompting. Recent tests by several forums users have seen this to speed up hotfix installation very noticeably, roughly shaving off one minute per hotfix. This is because each hotfix installation spends time searching for "third-party drivers" repeatedly one after another. Using /O will prevent this.

Please use this switch with caution as this may overwrite any driver files you choose to install. (although we've not heard any side effects from this since mentioning it here)

/N - Do not back up files for removal. This won't create any backups of older system files, thus there won't be any Add/Remove entries for the hotfixes.

/Z - Do not restart when installation is complete.

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