diff --git a/src/Squirrel/UpdateManager.InstallHelpers.cs b/src/Squirrel/UpdateManager.InstallHelpers.cs
index 4e9297013..a160e2e64 100644
--- a/src/Squirrel/UpdateManager.InstallHelpers.cs
+++ b/src/Squirrel/UpdateManager.InstallHelpers.cs
@@ -78,7 +78,7 @@ public async Task<RegistryKey> CreateUninstallerRegistryEntry(string uninstallCm
                 var stringsToWrite = new[] {
                     new { Key = "DisplayName", Value = zp.Title ?? zp.Description ?? zp.Summary },
                     new { Key = "DisplayVersion", Value = zp.Version.ToString() },
-                    new { Key = "InstallDate", Value = DateTime.Now.ToString("yyyymmdd") },
+                    new { Key = "InstallDate", Value = DateTime.Now.ToString("yyyyMMdd") },
                     new { Key = "InstallLocation", Value = rootAppDirectory },
                     new { Key = "Publisher", Value = String.Join(",", zp.Authors) },
                     new { Key = "QuietUninstallString", Value = String.Format("{0} {1}", uninstallCmd, quietSwitch) },