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Upload/save functionality
We currently use the roles Assetroles Office_Can_Replace and AssetUpload_New and Office_Can_Revise for Replace for determining whether a user is allowed to upload a new asset and replace an existing asset and upload a new asset, respectively, from the OC. These roles are not assigned to the light users out of the box, but they are assigned to the other user groups.
It is possible to disable uploads from the OC completely from the ConfigManager with the configuration option "Disable Office Connector uploads".
Debugging
To check if you have an issue with your manifest file, please try validating it with the following tool: https://github.com/OfficeDev/office-addin-validator.
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