How to Upload a Custom Logo to Multiple Extensions

Select the Setup tab and choose Manage under the Extensions section
Click the Bulk Modify Extensions button
Select the Digium Phones tab under Phone Settings
Choose the Idle Screen dropdown and navigate down to the Idle Screen section then select the Upload Picture icon

An Idle Screen Image logo must be a PNG image. The optimum dimensions are 205x85 but any image size can be accepted and scaled.

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