IOException: The process cannot access the file 'filename' because it is being used by another process

Hi everyone,
I'm having some difficulty with my File upload and File delete processes.
For the Upload, I do like:
sTempName = path + FileUpload1.FileName;
FileUpload1.PostedFile.SaveAs(sTempName); //sTempName = C:\Inetpub\vhosts\myfile.jpg
It works fine on my local machine, but once I upload it to my remote server, I sometimes (about 1 in 8 times) hit this exception:
System.IO.IOException: The process cannot access the file 'C:\Inetpub\vhosts\myfile.jpg' because it is being used by another process.
   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy)
   at System.IO.FileStream..ctor(String path, FileMode mode)
   at System.Web.HttpP ...