If you are using WSAM then you cannot access DFS file shares. Here's a what is says in he release notes from 6.3: "In Release 5.2, Juniper investigated support for DFS File Sharing through WSAM. However, we have identified that the system needs to trigger Domain Authentication via ICMP/Kerberos, and this functionality is currently not supported. Once Domain Authentication is fully supported through WSAM, there is a high probability Juniper can make DFS File sharing work. There is no ETA at the moment for supporting Domain Authentication. (30587)" As a workaround you can use the File access method to access the DFS shares.
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