In Google Oauth2 VBA authentication I showed how to use this class. All associated libraries are available in the cDataSet.xlsm library downloadable here, or through gistthat, as described here. You'll need the cRest module.
Here are some of the examples referred to in Google Oauth2 VBA authentication
A wrapper function is provided for access to the cOauth2 class. For now, only the Google Oauth2 is implemented.
This uses the CAPICOM object for DES encryption, which is only supported in Excel 32bit. Excel 64 bit is not encrypted
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