Vista - Unable to access higher level share folders

Here's the situation: I have a drive mapped on my XP machine at work, where we're using Novell. Our server team has set up a cifs share so we can map the drives in explorer. The J: drive is \\Pdxshrn104c\shr04\Eng. XP can access is fine, but on vista I get an access denied error. NOTE: Our server team won't help me because they don't support Vista. I would use XP but we can't find 64bit drivers for this machine.

More details: If I type in \Pdxshrn104c\shr04\Eng in explorer on XP, I see all the subfolders I have access to (and I can't see the folders I don't have access to). Then, again, if I browse to one of the lower level folders, I can get to another set of folders I have access to. In Vista, I get "access denied" for ENG and the next level of subfolders.

In Vista if I type in a path to a lower level folder which I have full read/write access to (we grant folder permissions at the sub-folder level using Novell), then Vista can access it.

Any ideas? I've contacted Microsoft, and their only solution is to grant full read/write permission to \\Pdxshrn104c\shr04\Eng. This is impossible as we have sensitive information that should not be accessed by everyone.

Sounds like a Novell interop issue. If the target machine has the client for Novell installed on it, technically it's no longer "XP". You may find something in the server-side logs which explains the "access denied" response being sent back to Vista.

Clarification: Neither machine has the Novell Client installed.

If a packet trace shows the Vista box getting back an access denied in response to its "Session Setup" or "Tree Connect" SMB requests, then the Novell server is nevertheless where you should start. There may be differences in the requests (obviously, since the outcome is different), but it's the server which returned the "access denied" that's got the interesting logs. Why is it denying access?