diff --git a/test/dotnet-watch.FunctionalTests/DotNetWatcherTests.cs b/test/dotnet-watch.FunctionalTests/DotNetWatcherTests.cs
index cc0a1c3fc0..65ff6416e2 100644
--- a/test/dotnet-watch.FunctionalTests/DotNetWatcherTests.cs
+++ b/test/dotnet-watch.FunctionalTests/DotNetWatcherTests.cs
@@ -39,15 +39,25 @@ namespace Microsoft.DotNet.Watcher.Tools.FunctionalTests
             var source = Path.Combine(_app.SourceDirectory, "Program.cs");
             var contents = File.ReadAllText(source);
             const string messagePrefix = "DOTNET_WATCH_ITERATION = ";
-            for (var i = 1; i <= 4; i++)
+            for (var i = 1; i <= 3; i++)
             {
                 var message = await _app.Process.GetOutputLineStartsWithAsync(messagePrefix, TimeSpan.FromMinutes(2));
                 var count = int.Parse(message.Substring(messagePrefix.Length), CultureInfo.InvariantCulture);
                 Assert.Equal(i, count);
 
-                File.Delete(source);
-                File.WriteAllText(source, contents);
-                await _app.HasRestarted();
+                await _app.IsWaitingForFileChange();
+
+                try
+                {
+                    File.SetLastWriteTime(source, DateTime.Now);
+                    await _app.HasRestarted();
+                }
+                catch
+                {
+                    // retry
+                    File.SetLastWriteTime(source, DateTime.Now);
+                    await _app.HasRestarted();
+                }
             }
         }
 
diff --git a/test/dotnet-watch.FunctionalTests/NoDepsAppTests.cs b/test/dotnet-watch.FunctionalTests/NoDepsAppTests.cs
index 22f46cbbe0..55d0441552 100644
--- a/test/dotnet-watch.FunctionalTests/NoDepsAppTests.cs
+++ b/test/dotnet-watch.FunctionalTests/NoDepsAppTests.cs
@@ -53,10 +53,19 @@ namespace Microsoft.DotNet.Watcher.Tools.FunctionalTests
             await _app.IsWaitingForFileChange();
 
             var fileToChange = Path.Combine(_app.SourceDirectory, "Program.cs");
-            var programCs = File.ReadAllText(fileToChange);
-            File.WriteAllText(fileToChange, programCs);
 
-            await _app.HasRestarted();
+            try
+            {
+                File.SetLastWriteTime(fileToChange, DateTime.Now);
+                await _app.HasRestarted();
+            }
+            catch
+            {
+                // retry
+                File.SetLastWriteTime(fileToChange, DateTime.Now);
+                await _app.HasRestarted();
+            }
+
             var pid2 = await _app.GetProcessId();
             Assert.NotEqual(pid, pid2);
             await _app.HasExited(); // process should exit after run