c2r64.dll is either not designed to run on windows or it contains an error

Question

c2r64.dll is either not designed to run on windows or it contains an error

Answer 1

The error that a specific Office DLL “is either not designed to run on Windows or it contains an error” typically indicates that the Office installation is damaged or that required DLLs or registry entries for VBA/Office components are corrupted.

For Microsoft 365/Office desktop apps, the supported fix is to repair or fully reinstall Office so that all DLLs and registry entries are restored:

1. Run an Online Repair of Office
   • On Windows 7 (similar steps apply in later versions via Settings → Apps → Installed apps):
     1. Open Control Panel → Programs and Features.
     2. Select the Microsoft Office product.
     3. Click Change.
     4. Select Online Repair, then Repair.
   • This reinstalls Office components and restores missing or corrupted VBA/Office DLLs.
2. If Online Repair fails or Office is in a broken/uninstallable state
   • Use the official Office uninstall troubleshooter (such as o15-ctrremove.diagcab) to completely remove the existing Office installation.
   • After the tool finishes, manually delete any remaining Office folders under C:\Program Files\Microsoft Office\ (for example, root\Office16) if they remain.
   • Restart Windows.
   • Reinstall Office from the account portal or original installer and activate it again.
3. If VBA-related errors also appear (macros disabled, VBE won’t load, or DLL errors like Vbe7)
   • These can be caused by third‑party registry cleaners or “system maintenance” tools removing Office/VBA registry keys.
   • Running Online Repair of Office restores those keys and re-enables VBA, macros, and the Visual Basic Editor.

If the issue persists after a clean uninstall and reinstall, contact Microsoft Support so they can use the uninstall tool and cleanup steps interactively, as in the referenced resolution.

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References:

• Office 2013 Visual Basic for Applications (VBA) errors
• Office 2021 desktop apps fail to open, cannot restore or uninstall - Microsoft Q&A