Excel 97 and windows 2000

OK heres a new one in my books. I dont know if anyone here has had this problem. If your running excel 97 and windows 2000 pro, and you see a .xls file and double click the file excel should open with no errors right? Well try it and an error will popup, here at work I have 150 machines and they all do this. The error states " A document with the name 'xxx.xls' is already open. You cannot open to documents witht he same name, even if the document are in diffrent folders. To open the second document, either close th ocumnet that's currently open or rename one of the documents" Now if you click OK it works great. But I found if its on the network and you open the document through a mapping it works fine. And also if you keep the excel file in the c: drive it works fine, but if its in any other directory this error messgae pops up wierd eh? My guess is its a windows 2000 and ofice 97 conflict. Any ideas?

nope no fix, only upgrading to office 2000 or 2001