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

Question

I have some code and when it executes, it throws a IOException, saying that

The process cannot access the file \'filename\' because it

Answer 1

I had the following scenario that was causing the same error:

• Upload files to the server
• Then get rid of the old files after they have been uploaded

Most files were small in size, however, a few were large, and so attempting to delete those resulted in the cannot access file error.

It was not easy to find, however, the solution was as simple as Waiting "for the task to complete execution":

using (var wc = new WebClient())
{
   var tskResult = wc.UploadFileTaskAsync(_address, _fileName);
   tskResult.Wait(); 
}