I can't install smap, I get this error

[m0v]

That's all I need! I'll install SMAPI now.
Game path: C:\Program Files (x86)\Stardew Valley
Color scheme: auto-detect
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Adding SMAPI files...
The installer failed with an unexpected exception.
If you need help fixing this error, see https://smapi.io/help

System.UnauthorizedAccessException: Access to the path 'C:\Program Files (x86)\Stardew Valley\smapi-internal' is denied.
at System.IO.FileSystem.CreateDirectory(String , Byte[] )
at StardewModdingApi.Installer.InteractiveInstaller.RecursiveCopy(FileSystemInfo source, DirectoryInfo targetFolder, Func`2 filter) in E:\source\_Stardew\SMAPI\src\SMAPI.Installer\InteractiveInstaller.cs:line 635
at StardewModdingApi.Installer.InteractiveInstaller.RecursiveCopy(FileSystemInfo source, DirectoryInfo targetFolder, Func`2 filter) in E:\source\_Stardew\SMAPI\src\SMAPI.Installer\InteractiveInstaller.cs:line 646
at StardewModdingApi.Installer.InteractiveInstaller.Run(String[] args) in E:\source\_Stardew\SMAPI\src\SMAPI.Installer\InteractiveInstaller.cs:line 378
at StardewModdingApi.Installer.Program.Main(String[] args) in E:\source\_Stardew\SMAPI\src\SMAPI.Installer\Program.cs:line 55
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