Errors when uploading and downloading using Sharepoint

[mariana_nsj]

I have Vista Home Premium loaded on my PC. I am trying to access a server using its Sharepoint front end. Often, and especially when using "Open folder using Windows Explorer" feature, I get error messages when trying to upload or download a file (error 0x80070057). This happens more with larger files, but it seems to be random what size file makes it happen. None of my colleagues who are not on Vista seem to have this problem. Today, I can download a 0.7MB file, but a 1.5MB file will not download.

Yesterday, tech support increased the timeout parameter for me to 30 minutes, allowing a 7MB file to upload when it wouldn't before. So, if I can now upload a 7MB, why can't I download a 1.5MB?

I was able to download the file today by opening it within Vista and using Save As, instead of trying to drag my file from folder to folder.

I'd like to be able to upload/download entire folders of files, including large ones.

Any ideas?