Configuration check failed for File/AzBlob connector

I’m unable to successfully create a source connection to Azure blob storage when using the File connector. My configuration is as follows:

Storage Provider → Storage account: https://{storageaccount}
SAS Token: {sas token}

URL: https://{storageaccount}{container}/{folderpath}/{file.csv}

Configuration check failed
Failed to load: azure://{storageaccount}{container}/{folderpath}/{file.csv}

You could have provided an invalid URL, please verify it: ServiceRequestError(‘<urllib3.connection.HTTPSConnection object at 0x7f670f024b80>: Failed to establish a new connection: [Errno -5] No address associated with hostname’).

The URL is 100% correct and has been tested using Storage Explorer.