I'm building a script that downloads a file from a URL and then executes it, but for some reason when I debug the script, it throws an error like:
System.ComponentModel.Win32Exception: 'An error occurred trying to start process "" with working directory "". The process cannot access the file because it is being used by another process.'

Here is my code:

```
using System.Net.Http;
using System.IO;
using System.Diagnostics;
String myUserName = Environment.UserName;
var httpClient = new HttpClient();
var responseStream = await httpClient.GetStreamAsync("http://exampleurl.com/examplefile.exe");
using var fileStream = new FileStream("C:/Users/"+myUserName+"/examplefile.exe", FileMode.Create);
responseStream.CopyTo(fileStream);
System.Threading.Thread.Sleep(10000); // sleeping waiting until download completes
string str = @"C:/Users/"+myUserName+"/examplefile.exe";
Process process = new Process();
process.StartInfo.FileName = str;
process.Start();

```