HP laptops have a reputation for feeling sluggish out of the box, and Antimalware Service Executable (MsMpEng.exe) hogging the CPU is one of the most common complaints. Before blaming the hardware or Defender itself, look at what HP puts on the machine: Support Assistant’s background tune-ups, HP update and analytics services, WMI providers polling hardware, and often an antivirus trial — all generating the constant file activity that Defender’s real-time protection dutifully inspects. Defender isn’t malfunctioning; it’s responding to the workload HP’s software creates.

The fix follows the familiar two-track pattern: quiet HP’s background noise, then tune Defender’s own workload with scheduling and exclusions. Open Task Manager > Processes, sort by CPU, and look for MsMpEng.exe alongside HP-named processes (HPSIsvc, HP Support Assistant, HP Analytics). For the brand-neutral version, see taming Antimalware Service Executable ; for trimming HP’s preload generally, see removing bloatware .

Why this happens

  • HP Support Assistant automation: Scheduled tune-ups, update checks, and health scans create Defender-scanned file activity.
  • HP telemetry and analytics services: Background data collection writing logs that get real-time scanned.
  • HP WMI provider activity: Hardware polling through WMI generates system activity Defender inspects.
  • Antivirus trial conflicts: Bundled McAfee/Norton trials fighting Defender for the same files.
  • Heavy factory preload: One of the industry’s larger bloatware bundles, each piece adding background services.
  • Default Defender scan timing: Full scans colliding with HP’s own scheduled maintenance.
  • Stale definitions or genuine threats: The usual Defender-side causes that apply on every brand.

How to fix it

Work through these in order — diagnose first, then act.

Fix 1: Survey the HP software landscape

Know what’s installed before removing anything.

  1. Open Settings > Apps > Installed apps and search “HP” — list everything: Support Assistant, JumpStart, Connection Optimizer, Documentation, plus any antivirus trial.
  2. In Task Manager > Details sorted by CPU, note HP-named processes running hot alongside MsMpEng.exe.
  3. Check Task Manager > Startup apps for HP entries and their impact ratings — these are the easiest wins.
  4. Look for a second antivirus (McAfee, Norton) — if present, that’s priority one (Fix 2).
  5. Decide per app: daily-useful (keep), occasionally useful (keep but disable auto-behavior), never-used (remove). Write down your removal candidates before acting.

Fix 2: Eliminate the antivirus conflict

The single biggest fix when it applies.

  1. If an antivirus trial is installed, choose one protector: keep the trial (letting it disable Defender properly) or remove it (letting Defender run alone). Never run both real-time engines.
  2. To remove: uninstall in Settings > Apps, then run the vendor’s official removal tool — leftover filter drivers from McAfee/Norton keep conflicting with Defender long after the standard uninstall.
  3. Verify Windows Security shows Microsoft Defender Antivirus as the active provider afterward.
  4. Reboot and observe Task Manager for 15 minutes — AV-conflict removal often halves MsMpEng.exe CPU immediately.
  5. If you keep the third-party product, schedule its full scans for idle hours — two products’ scheduled activity stacking up is what creates the worst spikes.

Fix 3: Put HP Support Assistant on a manual schedule

Keep the tool, lose the constant background work.

  1. Open HP Support Assistant > Settings and disable automatic updates, automatic tune-ups, and scheduled health scans — switch everything to manual.
  2. In Task Manager > Startup apps, disable HP Support Assistant and related HP startup entries — the app still works when you open it manually.
  3. Open Task Scheduler > Task Scheduler Library > Hewlett-Packard (or HP) and disable or reschedule the automated tasks to a monthly cadence that suits you.
  4. Use Support Assistant deliberately once a month: run updates, run the tune-up, then close it — you get the benefits with none of the background cost.
  5. Get drivers by model from HP’s official support site whenever you prefer manual control — the site works fine without the assistant.

Fix 4: Debloat the HP factory preload

Remove what you’ll never use.

  1. Uninstall from Settings > Apps: HP JumpStart, HP Connection Optimizer (unless you use its features), HP Documentation, preinstalled games, and duplicate utilities.
  2. Keep: audio/network drivers, HP Power Manager or equivalent if you use battery features, and anything tied to function keys or the fingerprint reader.
  3. After uninstalling, check Services (services.msc) for orphaned HP services from removed apps and set them to Disabled.
  4. Check Task Scheduler for leftover HP tasks from uninstalled apps and delete them.
  5. Reboot and compare idle Task Manager — fewer HP services means less file activity for Defender to scan, full stop.

Fix 5: Reschedule Defender scans

Standard tuning that matters on HP’s busy preload.

  1. Open Task Scheduler (taskschd.msc) > Task Scheduler Library > Microsoft > Windows > Windows Defender.
  2. Set Windows Defender Scheduled Scan to an away time like 3 AM via Properties > Triggers.
  3. Under Conditions, enable Start only if idle and Stop if the computer ceases to be idle.
  4. Stagger the scan away from any remaining HP scheduled tasks so maintenance doesn’t pile up.
  5. Enable Run as soon as possible after a scheduled start is missed to clear backlogs overnight.

Fix 6: Exclude HP churn folders and your busy folders

Break the rescan cycle.

  1. Use Resource Monitor > Disk to confirm which HP paths Defender scans repeatedly — usually under C:\ProgramData\HP and HP log directories.
  2. Go to Windows Security > Virus & threat protection > Manage settings > Exclusions > Add an exclusion > Folder and add the verified HP data/log folders.
  3. Add your own high-churn folders: code projects, game libraries, VM images, cloud-sync folders.
  4. Add Process exclusions for trusted heavy tools if they drive spikes.
  5. Never exclude Downloads, Temp, or system folders — see Microsoft’s Windows Security guidance for exclusion best practices.

Fix 7: Update everything, then verify

Close the loop with current software.

  1. Windows Security > Virus & threat protection > Protection updates > Check for updates.
  2. Install all pending Windows Update items — Defender platform improvements ship through it.
  3. Update HP drivers and BIOS via HP Support Assistant (manual run) or HP’s support site — current firmware reduces the low-level system churn that amplifies every CPU symptom.
  4. Run one overnight Full scan to establish a clean baseline, then reboot.
  5. Observe for a full workday: MsMpEng.exe should spike briefly on new files and otherwise stay quiet. If it doesn’t, re-check for a second AV or a stuck scan in Protection history.

Closing

HP’s heavy software preload is the reason Defender works so hard on HP laptops — Support Assistant’s automation, telemetry services, bundled AV trials, and a dozen background utilities all feed Microsoft’s scanner a constant stream of file activity. Strip the preload to what you actually use, schedule what’s left, tune Defender’s own workload, and the CPU graph calms down. The laptop was never slow; it was just busy doing things you never asked for.

Frequently asked questions

What HP software makes Defender work harder?
HP Support Assistant, HP Update Service, HP Analytics service, and various HP WMI providers run background tasks — update checks, telemetry uploads, and hardware polling — that generate file activity Microsoft Defender inspects in real time. HP laptops also tend to ship with more preinstalled utilities than average, each adding its own background services. The hardware is fine; it is the bundled software stack multiplying Defender’s workload that causes the high CPU.
Is HP Support Assistant safe to disable or remove?
Disabling its automatic behavior is safe and recommended if you do not use it: turn off automatic updates and tune-ups inside the app, or disable it from Startup apps. Full removal is also safe — drivers remain available from HP’s support website — but you lose convenient automated driver updates and warranty-status checks. Most users do best keeping it installed but on a manual schedule rather than letting it run constantly.
Why do HP laptops seem slower than other brands out of the box?
It is the preload, not the hardware. HP’s factory image historically includes one of the heaviest utility bundles among major brands: Support Assistant, JumpStart, Connection Optimizer, documentation apps, antivirus trials, and third-party offers. Each adds startup entries and background services. A thorough debloat of a new HP laptop — removing what you will never use — typically produces the single biggest performance improvement available, Defender CPU included.
Do HP's BIOS updates affect Defender CPU usage?
Indirectly. HP BIOS and firmware updates delivered through Support Assistant or Windows Update change low-level hardware behavior, and the update process itself generates file activity Defender scans. More importantly, outdated BIOS versions can cause excessive system interrupts or poor power management that keeps the CPU busy overall, making Defender’s share feel worse. Keeping BIOS reasonably current via HP’s support site is good hygiene, though not a direct Defender fix.