Last updated: January 21, 2026
To resolve this error:
- Copy and paste %localappdata% into your Start menu in Windows and press Enter.
- Navigate to the Apps folder and delete the 2.0 folder.
- Attempt to install the HubSpot Sales Outlook desktop add-in again.
- If this doesn't resolve the error, return to %localappdata% and delete the following folders:
- IsolatedStorage
- assembly
- Attempt to install the HubSpot Sales Outlook desktop add-in again.
Please note: if you encounter an error message that the folder or file(s) are currently in use when you attempt to delete them, close all instances of Outlook and HubSpot for Windows. Press Ctrl + Alt + Delete on your keyboard and click Task Manager. Ensure you are in the Processes tab, then locate and right-click the SidekickTrayWPF process and click End Task. Then, attempt to delete the folder or file(s) again.