Sysinternals
Autoruns
The honest answer to "why is this PC slow to start?" Autoruns lists everything set to launch at boot or sign-in: Run keys, startup folders, services, scheduled tasks, Explorer shell extensions, drivers and more, far beyond what Task Manager's Startup tab shows.
Tick Hide Signed Microsoft Entries and what remains is the third-party clutter worth questioning. Untick an entry to disable it rather than delete it, so a mistake is easy to undo. It can also check signatures and look up file hashes on VirusTotal. This is the tool that replaces every paid startup optimizer.
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