Office 2007 network error - not writing to net disk

[crcanassr]

We just upgraded Office 2003 to 2007 and now we can not write to network disks. This is an Office 2007 problem only as other apps. work fine. We get a network error, network not responding error. We are running Windows XP Pro on the work stations and Small Business Server 2003 on the server. We have 20 workstations. We need to write to a server share as it is our policy to keep all data files on the server. Right now users are writing their documents to a local drive and then copying then to the network disk (no problems there) but this is not acceptable. We are even thinking on going back to 2003 but this will require us to convert all 2007 documents to 2003 format. I have researched other forums and I have seen people complaining about this problem but I have not found any answers. No, it is not the AV program, we already tried disabling and even uninstalling it. Yes, we have tried Vista, same results. Right now we are weary of any upgrades as we already paid for 20 Office 2007 licenses and MS does not offer refunds......

Thanks for your help