Connection Failed on OSX 10.7.5

A few days ago,  the WD My Cloud suddenly cannot be connected with Mac Finder. It’s not a problem to a certain computer but all Macs in our office cannot establish the connection successfully. It shows “Connection failed” in the Finder.

Screen Shot 2014-08-22 at 6.11.54 PM.png

We have already rebooted the drive, try shutting it down and started up again, clear all caches on our computers but still cannot connect to it. However, it can be connect via smb:// 

Screen Shot 2014-08-22 at 6.12.39 PM.png

But failed if we connect if via afp://

Screen Shot 2014-08-22 at 6.13.59 PM.png

I cannot find anything related to this on the WD knowledge base nor this community. Does anybody have this experience before? Any solution to this? We haven’t changed anything before this happened. No firmware updated, no setting changes. It just suddenly drop connection and none of the Macs in the office can access it normally.

Please let me know if anyone has a clue to solve this. Thanks!

Hello,

Has anything been changed in regards to your network security, like firewall or antivirus?