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All Tiers
Install the Send2CRM Essentials Salesforce package:
https://login.salesforce.com/packaging/installPackage.apexp?p0=04tDo0000000zcUIAQ04tDo0000000zfxIAA
We recommend installing the package for admin users only. The necessary permissions for other users can then be easily applied using the included permission set.
Professional, Advanced, Enterprise
After installation of the Essentials package above, install the Send2CRM Analytics package:
https://login.salesforce.com/packaging/installPackage.apexp?p0=04tDo0000000zgCIAQ
Again this should be installed for admin users only. The included permission sets should be assigned after installation.