diff --git a/ProjBobcat/ProjBobcat/Class/Helper/CryptoHelper.cs b/ProjBobcat/ProjBobcat/Class/Helper/CryptoHelper.cs
index b306f0cd..37c94eb6 100644
--- a/ProjBobcat/ProjBobcat/Class/Helper/CryptoHelper.cs
+++ b/ProjBobcat/ProjBobcat/Class/Helper/CryptoHelper.cs
@@ -18,7 +18,7 @@ public static class CryptoHelper
     /// <returns></returns>
     public static async Task<string> ComputeFileHashAsync(string path, HashAlgorithm hashAlgorithm)
     {
-        await using var fs = File.OpenRead(path);
+        await using var fs = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
         var retVal = await hashAlgorithm.ComputeHashAsync(fs);
 
         return BitConverter.ToString(retVal).Replace("-", string.Empty);
@@ -32,8 +32,8 @@ public static async Task<string> ComputeFileHashAsync(string path, HashAlgorithm
     /// <returns></returns>
     public static string ComputeFileHash(string path, HashAlgorithm hashAlgorithm)
     {
-        var bytes = File.ReadAllBytes(path);
-        var retVal = hashAlgorithm.ComputeHash(bytes);
+        using var fs = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
+        var retVal = hashAlgorithm.ComputeHash(fs);
 
         return BitConverter.ToString(retVal).Replace("-", string.Empty);
     }
diff --git a/ProjBobcat/ProjBobcat/Class/Helper/DownloadHelper.cs b/ProjBobcat/ProjBobcat/Class/Helper/DownloadHelper.cs
index 18c28ad5..20e5e423 100644
--- a/ProjBobcat/ProjBobcat/Class/Helper/DownloadHelper.cs
+++ b/ProjBobcat/ProjBobcat/Class/Helper/DownloadHelper.cs
@@ -19,12 +19,7 @@ namespace ProjBobcat.Class.Helper;
 /// </summary>
 public static class DownloadHelper
 {
-    const int BufferSize = 1024 * 1024 * 5;
-
-    /// <summary>
-    ///     获取或设置用户代理信息。
-    /// </summary>
-    public static string Ua { get; set; } = "ProjBobcat";
+    const int BufferSize = 1024;
 
     /// <summary>
     ///     下载线程
@@ -108,7 +103,7 @@ public static async Task DownloadData(DownloadFile downloadProperty, Cancellatio
             using var res = await DataClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, ct);
 
             await using var stream = await res.Content.ReadAsStreamAsync(ct);
-            await using var fileToWriteTo = File.Create(filePath);
+            await using var fileToWriteTo = File.Open(filePath, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
 
             var responseLength = res.Content.Headers.ContentLength ?? 0;
             var downloadedBytesCount = 0L;
@@ -319,7 +314,7 @@ public static async Task MultiPartDownloadTaskAsync(DownloadFile downloadFile, i
 
                 await using (var stream = await res.Content.ReadAsStreamAsync(cts.Token))
                 {
-                    await using var fileToWriteTo = File.OpenWrite(t.Item2.TempFileName);
+                    await using var fileToWriteTo = File.Open(t.Item2.TempFileName, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
                     var buffer = new byte[BufferSize];
                     var sw = new Stopwatch();
 
@@ -352,7 +347,6 @@ public static async Task MultiPartDownloadTaskAsync(DownloadFile downloadFile, i
                     sw.Stop();
 
                     await fileToWriteTo.FlushAsync();
-                    fileToWriteTo.Close();
                 }
 
                 Interlocked.Add(ref tasksDone, 1);
@@ -392,16 +386,14 @@ public static async Task MultiPartDownloadTaskAsync(DownloadFile downloadFile, i
                 return;
             }
 
-            await using (var outputStream = File.Create(filePath))
+            await using (var outputStream = File.Open(filePath, FileMode.Create, FileAccess.Write, FileShare.ReadWrite))
             {
                 foreach (var inputFilePath in readRanges)
                 {
-                    await using var inputStream = File.OpenRead(inputFilePath.TempFileName);
+                    await using var inputStream = File.Open(inputFilePath.TempFileName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
                     outputStream.Seek(inputFilePath.Start, SeekOrigin.Begin);
                     await inputStream.CopyToAsync(outputStream, cts.Token);
 
-                    inputStream.Close();
-
                     File.Delete(inputFilePath.TempFileName);
                 }
 
diff --git a/ProjBobcat/ProjBobcat/Class/Helper/HttpClientHelper.cs b/ProjBobcat/ProjBobcat/Class/Helper/HttpClientHelper.cs
index 30ea12d3..1c5ae10e 100644
--- a/ProjBobcat/ProjBobcat/Class/Helper/HttpClientHelper.cs
+++ b/ProjBobcat/ProjBobcat/Class/Helper/HttpClientHelper.cs
@@ -14,6 +14,11 @@ public static class HttpClientHelper
     public const string HeadClientName = "HeadClient";
     public const string MultiPartClientName = "MultiPartClient";
 
+    /// <summary>
+    ///     获取或设置用户代理信息。
+    /// </summary>
+    public static string Ua { get; set; } = "ProjBobcat";
+
     public static IHttpClientFactory HttpClientFactory { get; private set; }
 
     public static void Init()
@@ -21,7 +26,10 @@ public static void Init()
         var arr = new[] {DefaultClientName, DataClientName, HeadClientName, MultiPartClientName};
         foreach (var name in arr)
             ServiceHelper.ServiceCollection
-                .AddHttpClient(name)
+                .AddHttpClient(name, client =>
+                {
+                    client.DefaultRequestHeaders.UserAgent.ParseAdd(Ua);
+                })
                 .ConfigurePrimaryHttpMessageHandler(_ => new HttpClientHandler
                 {
                     AllowAutoRedirect = false
diff --git a/ProjBobcat/ProjBobcat/Class/Helper/RandomHelper.cs b/ProjBobcat/ProjBobcat/Class/Helper/RandomHelper.cs
index 0b78eb63..d74f8d7c 100644
--- a/ProjBobcat/ProjBobcat/Class/Helper/RandomHelper.cs
+++ b/ProjBobcat/ProjBobcat/Class/Helper/RandomHelper.cs
@@ -73,9 +73,7 @@ public static void Shuffle<T>(this IList<T> list)
         {
             n--;
             var k = RandomInteger(0, n);
-            var value = list[k];
-            list[k] = list[n];
-            list[n] = value;
+            (list[k], list[n]) = (list[n], list[k]);
         }
     }
 }
\ No newline at end of file
diff --git a/ProjBobcat/ProjBobcat/DefaultComponent/Authenticator/MicrosoftAuthenticator.cs b/ProjBobcat/ProjBobcat/DefaultComponent/Authenticator/MicrosoftAuthenticator.cs
index 5dfb45c9..c0fddb8f 100644
--- a/ProjBobcat/ProjBobcat/DefaultComponent/Authenticator/MicrosoftAuthenticator.cs
+++ b/ProjBobcat/ProjBobcat/DefaultComponent/Authenticator/MicrosoftAuthenticator.cs
@@ -398,7 +398,7 @@ public static object ResolveMSGraphResult<T>(string content)
 
     public static string GetLoginUri(string clientId, string redirectUri)
     {
-        return Uri.EscapeUriString("https://login.live.com/oauth20_authorize.srf"
+        return Uri.EscapeDataString("https://login.live.com/oauth20_authorize.srf"
                                    + $"?client_id={clientId}"
                                    + "&response_type=code"
                                    + $"&scope={MSAuthScope}"