[171221 10:58:37] You have not provided a valid Google Cloud JSON configuration (googlestorage.json) in the configuration page. As a result I cannot upload anything to Google Storage. Please fix this issue and try backing up again.
[171221 10:58:37] Failed to process file <root>/administrator/components/com_akeeba/backup/site-www.####-20171221-095712.zip
[171221 10:58:37] Error received from the post-processing engine:
[171221 10:58:37] You have not provided a valid Google Cloud JSON configuration (googlestorage.json) in the configuration page. As a result I cannot upload anything to Google Storage. Please fix this issue and try backing up again. \n Failed to process file <root>/administrator/components/com_akeeba/backup/site-www.####-20171221-095712.zip
[171221 10:58:37] Post-processing interrupted -- no more files will be transferred
The key is valid. I've tested it with different sites (and versions of akeeba). I alos created a new key, but akeeba backup always says that it isn't valid.
Thanks for your help!