Error 100 causes installation failure

Last updated on Dec 9, 2025

Learn how to resolve error code 100 "gccustomhook could not be found" during app installation.

Error code 100 occurs when the installer cannot find the gccustomhook file required to verify or update Adobe Genuine Service. This missing file prevents Creative Cloud apps from installing on your system.

Missing gccustomhook file

To resolve this issue, refresh the Creative Cloud desktop app so that it can automatically repair the missing file.

Open the Creative Cloud desktop app.

Select the Apps tab in the left pane.

Creative Cloud desktop app showing a list of installed and available Adobe apps. — View and open the apps included in your plan.

In the upper-right corner, select Check for updates.

Creative Cloud desktop app showing the Installed apps section on the right, with the More options menu expanded and the Check for updates option highlighted. — Select Check for updates to manually look for the latest app versions.

After the check completes, the app automatically restores the missing Adobe Genuine Service file.

Errors 101, 103, and 106 cause installation failure

Learn

Learn with step-by-step video tutorials and hands-on guidance right in the app.

Community

Join discussions, find answers, learn from experts, and share your knowledge.

Adobe Home

Access your favorite Creative Cloud apps, services, file management, and more.