Office 365 Apps Not Responding or Freezing on Startup (2025 Fix)
Are your Office 365 apps freezing or not responding when you launch them? You're not alone. Many Windows 11 and 10 users report that Word, Excel, Outlook, and PowerPoint get stuck on startup after system or Office updates. This guide walks you through verified fixes that restore smooth performance without reinstalling Office.
🔍 Common Causes of Office 365 Freezes
- Corrupted Office installation or missing components.
- Conflicting third-party add-ins in Outlook or Word.
- Outdated COM Add-ins or antivirus interference.
- Damaged user profiles or registry entries.
- Hardware graphics acceleration causing app hangs.
⚙️ Step 1 – Start Office in Safe Mode
Launching Office in Safe Mode disables extensions and helps isolate the culprit. Press Win + R and type:
winword /safe
or for Outlook:
outlook /safe
If the app opens normally, the issue lies with add-ins. Go to File → Options → Add-ins → COM Add-ins → Go and disable all extensions, then re-enable them one by one.
⚙️ Step 2 – Run Quick Repair or Online Repair
Microsoft 365 includes a self-repair tool:
- Open Control Panel → Programs → Programs and Features.
- Select Microsoft 365 Apps → Change → Quick Repair.
- If problems persist, choose Online Repair for a deeper fix (requires internet).
⚙️ Step 3 – Disable Hardware Graphics Acceleration
GPU acceleration improves visuals but sometimes triggers freezes. In any Office app → File → Options → Advanced → check Disable hardware graphics acceleration → Restart the app.
⚙️ Step 4 – Clear the Office Cache & Credential Manager
Corrupt cache files often cause startup hangs:
- Navigate to
%localappdata%\Microsoft\Office\16.0\and delete theOfficeFileCachefolder. - Open Control Panel → Credential Manager → Windows Credentials → remove all MicrosoftOffice entries.
⚙️ Step 5 – Repair User Profile & Registry
If freezes continue, create a new Windows user profile or reset registry keys for Office:
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0
Rename the folder to 16.0.old and restart. Office will recreate default keys.
⚙️ Step 6 – Update Office & Windows
Out-of-date builds trigger compatibility bugs. Open any Office app → File → Account → Update Options → Update Now. Ensure Windows Update is also enabled to pull patches that fix hangs and crashes.
🧰 Advanced Fix – Rebuild Office Licensing Service
If apps remain unresponsive, re-register the Office Click-to-Run service:
sc config ClickToRunSvc start= auto net start ClickToRunSvc
Then restart your PC and open any Office program again.
