diff --git a/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs b/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs
index af3ea5f..2a00598 100644
--- a/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs
+++ b/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs
@@ -64,6 +64,21 @@ public partial class ServiceChannelService
         }
     }
 
+    /// <summary>
+    /// 更新时若目标名称被软删记录占用，则改名释放唯一键，避免 uk_scg_name 冲突。
+    /// </summary>
+    private async Task FreeSoftDeletedNameIfNeededAsync(string name, int currentId)
+    {
+        var conflict = await ServiceChannelGroupRepository.GetByNameIncludingDeletedAsync(name);
+        if (conflict == null || !conflict.IsDeleted || conflict.Id == currentId)
+        {
+            return;
+        }
+
+        conflict.Name = $"{name}__deleted_{conflict.Id}";
+        await ServiceChannelGroupRepository.UpdateAsync(conflict);
+    }
+
     /// <summary>
     /// 校验渠道编码唯一性。
     /// </summary>
diff --git a/src/Oms.Application/Services/Channels/ServiceChannelService.cs b/src/Oms.Application/Services/Channels/ServiceChannelService.cs
index dea8476..7188468 100644
--- a/src/Oms.Application/Services/Channels/ServiceChannelService.cs
+++ b/src/Oms.Application/Services/Channels/ServiceChannelService.cs
@@ -128,9 +128,21 @@ public partial class ServiceChannelService : ApplicationService
     public async Task CreateGroupAsync(ServiceChannelGroupSaveInput input)
     {
         await ValidateGroupInputAsync(input, null);
+        var name = input.Name.Trim();
+        var deleted = await ServiceChannelGroupRepository.GetByNameIncludingDeletedAsync(name);
+        if (deleted != null && deleted.IsDeleted)
+        {
+            deleted.IsDeleted = false;
+            deleted.Name = name;
+            deleted.AppId = input.AppId;
+            deleted.ApiServiceProviderId = input.ApiServiceProviderId;
+            await ServiceChannelGroupRepository.UpdateAsync(deleted);
+            return;
+        }
+
         await ServiceChannelGroupRepository.InsertAsync(new ServiceChannelGroup
         {
-            Name = input.Name.Trim(),
+            Name = name,
             AppId = input.AppId,
             ApiServiceProviderId = input.ApiServiceProviderId
         });
@@ -146,7 +158,9 @@ public partial class ServiceChannelService : ApplicationService
     {
         var group = await GetGroupOrThrowAsync(input.Id);
         await ValidateGroupInputAsync(input, group.Id);
-        group.Name = input.Name.Trim();
+        var name = input.Name.Trim();
+        await FreeSoftDeletedNameIfNeededAsync(name, group.Id);
+        group.Name = name;
         group.AppId = input.AppId;
         group.ApiServiceProviderId = input.ApiServiceProviderId;
         await ServiceChannelGroupRepository.UpdateAsync(group);
diff --git a/src/Oms.Application/Services/Storage/FileStorageService.cs b/src/Oms.Application/Services/Storage/FileStorageService.cs
index 9223b0e..1c256d0 100644
--- a/src/Oms.Application/Services/Storage/FileStorageService.cs
+++ b/src/Oms.Application/Services/Storage/FileStorageService.cs
@@ -245,6 +245,32 @@ public class FileStorageService : ApplicationService
             return "text/html; charset=utf-8";
         }
 
+        if (path.EndsWith(".png", StringComparison.OrdinalIgnoreCase))
+        {
+            return "image/png";
+        }
+
+        if (path.EndsWith(".webp", StringComparison.OrdinalIgnoreCase))
+        {
+            return "image/webp";
+        }
+
+        if (path.EndsWith(".gif", StringComparison.OrdinalIgnoreCase))
+        {
+            return "image/gif";
+        }
+
+        if (path.EndsWith(".bmp", StringComparison.OrdinalIgnoreCase))
+        {
+            return "image/bmp";
+        }
+
+        if (path.EndsWith(".jpg", StringComparison.OrdinalIgnoreCase)
+            || path.EndsWith(".jpeg", StringComparison.OrdinalIgnoreCase))
+        {
+            return "image/jpeg";
+        }
+
         return "application/octet-stream";
     }
 
diff --git a/src/Oms.Application/Storage/TencentCosFileStorage.cs b/src/Oms.Application/Storage/TencentCosFileStorage.cs
index 9f152d7..017c170 100644
--- a/src/Oms.Application/Storage/TencentCosFileStorage.cs
+++ b/src/Oms.Application/Storage/TencentCosFileStorage.cs
@@ -365,8 +365,11 @@ public sealed class TencentCosFileStorage : IFileStorage, IDisposable
         if (!string.IsNullOrWhiteSpace(_customHost)
             && !_customHost.EndsWith(".myqcloud.com", StringComparison.OrdinalIgnoreCase))
         {
+            // 自定义 CDN 域名：URL 走 cos.ideship.com，但不要把 Host 签进 q-header-list。
+            // signHost=true 时浏览器直开签名链常因 CDN 回源 Host 不一致而 403（img naturalWidth=0），
+            // 对象其实在桶里（/file-storage/stream 可读）。
             preSign.host = _customHost;
-            preSign.signHost = true;
+            preSign.signHost = false;
         }
     }
 
diff --git a/src/Oms.Domain/ChannelsAggregate/Repositories/IServiceChannelGroupRepository.cs b/src/Oms.Domain/ChannelsAggregate/Repositories/IServiceChannelGroupRepository.cs
index 749f4a0..021cd8f 100644
--- a/src/Oms.Domain/ChannelsAggregate/Repositories/IServiceChannelGroupRepository.cs
+++ b/src/Oms.Domain/ChannelsAggregate/Repositories/IServiceChannelGroupRepository.cs
@@ -6,4 +6,9 @@ namespace Oms.Domain.ChannelsAggregate.Repositories;
 public interface IServiceChannelGroupRepository : IRepository<ServiceChannelGroup>
 {
     Task<ServiceChannelGroup?> GetByNameAsync(string name, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// 按名称查询分组（含软删除），用于唯一名冲突时恢复或释放名称。
+    /// </summary>
+    Task<ServiceChannelGroup?> GetByNameIncludingDeletedAsync(string name, CancellationToken cancellationToken = default);
 }
diff --git a/src/Oms.SqlSugarCore/Channels/ServiceChannelGroupRepository.cs b/src/Oms.SqlSugarCore/Channels/ServiceChannelGroupRepository.cs
index 22c5b78..cf6ddd2 100644
--- a/src/Oms.SqlSugarCore/Channels/ServiceChannelGroupRepository.cs
+++ b/src/Oms.SqlSugarCore/Channels/ServiceChannelGroupRepository.cs
@@ -2,6 +2,7 @@ using Fake.DependencyInjection;
 using Oms.Domain.ChannelsAggregate.Entities;
 using Oms.Domain.ChannelsAggregate.Repositories;
 using Oms.SqlSugarCore.Repositories;
+using SqlSugar;
 
 namespace Oms.SqlSugarCore.Channels;
 
@@ -11,4 +12,17 @@ public class ServiceChannelGroupRepository : OmsSqlSugarRepository<ServiceChanne
     {
         return FirstOrDefaultAsync(x => x.Name == name, cancellationToken);
     }
+
+    public async Task<ServiceChannelGroup?> GetByNameIncludingDeletedAsync(
+        string name,
+        CancellationToken cancellationToken = default)
+    {
+        var db = await GetDbContextAsync(cancellationToken);
+        var rows = await db.Queryable<ServiceChannelGroup>()
+            .ClearFilter()
+            .Where(x => x.Name == name)
+            .Take(1)
+            .ToListAsync(cancellationToken);
+        return rows.FirstOrDefault();
+    }
 }