I have a Windows 2008 R2 64bit server that can’t map a drive to the drobo share.
I have tried manually and through the drobo dashboard, neither work.
I can map to other shares (windows 7, 2k8 or 2k12.)
I can map to the drobo from other computers using the dashboard or mapping a drive without issue.
I have the firewall disabled on the 2k8 server with the problem, and I have plugged it directly into the server and it still doesn’t work, however I can ping it and I can administer it from the drobo dashboard.
I ran into this exact problem and it took me the last 3 weeks to figure it out. If this setting is enabled in your computer/domain policy, disable it:
Microsoft network client: Digitally sign communications (always)