Fix Office 365 Slow Performance After Update (2025 Guide)

Is your Office 365 running slow after the latest Windows or Microsoft 365 update? Word takes forever to load, Excel freezes while editing sheets, Outlook becomes sluggish, or PowerPoint crashes randomly?

This is happening to thousands of users after recent patches — but the good news is: you can fix it using safe, verified solutions tested in real Office 365 environments.

Before you start: If your Office apps are freezing, lagging, crashing, or loading extremely slow, follow the step-by-step fixes below. These solutions work on Windows 10, Windows 11, and Microsoft 365 (2025 versions).

⭐ Why Does Office 365 Become Slow After an Update?

Recent Microsoft updates often change internal configurations, which may cause:

• 🔸 Conflicts with old Office cache files
• 🔸 Damaged or partially updated Office components
• 🔸 Background indexing running nonstop
• 🔸 Add-ins becoming incompatible after updates
• 🔸 High CPU usage due to Office Telemetry
• 🔸 Graphics acceleration conflicts after patches

You don’t have to uninstall Office — follow the fixes below and your apps will run smoothly again.

✅ Fix 1 — Disable Hardware Graphics Acceleration

This is the #1 cause why Word, Excel, and Outlook lag after updates.

Steps:

1. Open any Office app (Word/Excel/Outlook).
2. Go to File → Options.
3. Select Advanced.
4. Scroll down to the Display section.
5. Enable: Disable hardware graphics acceleration.
6. Click OK and restart Office apps.

This alone fixes lag for many users.

✅ Fix 2 — Repair Office 365 (Quick Repair)

1. Press Windows + R, type appwiz.cpl, hit Enter.
2. Select Microsoft 365 Apps.
3. Click Modify.
4. Select Quick Repair.
5. Wait 2–3 minutes.

If the issue remains, run: Online Repair → Full reset of Office files (without deleting your data).

✅ Fix 3 — Reset Office Cache & Temporary Files

Office builds up large cache folders which become corrupted after updates.

Steps:

1. Press Windows + R, type: %localappdata%\Microsoft\Office\
2. Delete folders:

• 16.0\OfficeFileCache
• Office\Telemetry

Restart Office — apps will rebuild fresh cache.

✅ Fix 4 — Disable Unnecessary Add-ins

After updates, outdated add-ins slow down Word, Excel, and Outlook.

Steps:

1. Open Word / Excel / Outlook
2. Go to File → Options → Add-ins
3. At the bottom, choose COM Add-ins → Click Go
4. Uncheck everything except Microsoft defaults

Restart the app — speed improves immediately.

✅ Fix 5 — Reset Office Activation Tokens

Sometimes activation errors silently slow down Office.

Run this command in CMD (Admin):

cd %systemroot%\System32\spp\
cscript slmgr.vbs /rearm

Then restart your PC.

✅ Fix 6 — Turn Off Cloud Optimized Features

Cloud integration slows down systems with slow internet.

Go to:

1. File → Options → Save
2. Disable: AutoSave and Keep documents on OneDrive

This improves speed on slower networks.

📌 Bonus Fix — Delete Old Office Registry Keys

Only safe if done carefully.

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common

Delete subfolders:

• ExperimentEcs
• ExperimentTas

This refreshes experimental features causing slowdowns.

🔗 Related Guides

• Fix Office 365 Search Not Working After Update
• Fix Office 365 Login Problems
• Microsoft 365 Apps Crashing After Update

❇ WhatsApp Support (Fastest Response)

🧩 Conclusion

Office 365 becoming slow or unresponsive after an update is one of the most common issues in 2025. The good news — these fixes are proven, safe, and work for majority of users.

If your apps are still slow, freezing, or crashing, feel free to reach out using the WhatsApp button above for live troubleshooting.