My license for Trados Studio 2021 and 2019 is normal.

Trados Studio 2021 and 2019 are activated at present.

This Trados Studio  2021 is updated from Trados Studio 2019. I made a side-by-side installation for Trados Studio 2021 and 2019.

However, when I create a project in Trados Studio 2021 for the first time, the bilingual files cannot open in Trados Studio 2021. But when I transfer this project package to another computer with Trados Studio 2019 installed, it can be normally open.

Here attached with the error message:

<SDLErrorDetails time="12/1/2020 9:13:47 AM">
<ErrorMessage>Could not load file or assembly 'CompactEncodingDetector.dll' or one of its dependencies. The specified module could not be found.</ErrorMessage>
<Exception>
<Type>System.IO.FileNotFoundException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</Type>
<FileName>CompactEncodingDetector.dll</FileName>
<FusionLog />
<HelpLink />
<Source>ManagedCompactEncodingDetector</Source>
<HResult>-2147024770</HResult>
<StackTrace><![CDATA[ at ManagedCompactEncodingDetector.EncodingDetector..ctor()
at Sdl.FileTypeSupport.Framework.Core.Utilities.FileEncoding.Detect(String filePath, Encoding suggestedEncoding, String& lineBreakType, Boolean& hasUTF8BOM)
at Sdl.FileTypeSupport.Native.FrameMaker.FileFormat.MifParser.MakerDocument.CreateDocumentCollection()
at Sdl.FileTypeSupport.Native.FrameMaker.FrameworkImpl.Extractor.ParserImpl.GetDocumentCollection()
at Sdl.FileTypeSupport.Native.FrameMaker.FrameworkImpl.Extractor.ParserImpl.Parse()
at Sdl.FileTypeSupport.Native.FrameMaker.FrameworkImpl.Extractor.FileParser.DuringParsing()
at Sdl.FileTypeSupport.Framework.NativeApi.AbstractNativeFileParser.ParseNext()
at Sdl.FileTypeSupport.Framework.Integration.FileExtractor.ParseNext()
at Sdl.FileTypeSupport.Framework.Integration.MultiFileConverter.ParseNext()
at Sdl.FileTypeSupport.Framework.Integration.MultiFileConverter.Parse()
at Sdl.ProjectApi.AutomaticTasks.Conversion.ConversionTask.ProcessFile(IExecutingTaskFile executingTaskFile)
at Sdl.ProjectApi.AutomaticTasks.AbstractFileLevelAutomaticTaskImplementation.Execute()]]></StackTrace>
</Exception>
<Environment>
<ProductName>SDL Trados Studio</ProductName>
<ProductVersion>15.0.0.0</ProductVersion>
<EntryAssemblyFileVersion>15.2.7.2849</EntryAssemblyFileVersion>
<OperatingSystem>Microsoft Windows 7 Ultimate </OperatingSystem>
<ServicePack>Service Pack 1</ServicePack>
<OperatingSystemLanguage>1033</OperatingSystemLanguage>
<CodePage>1252</CodePage>
<LoggedOnUser>TR-PUB\Administrator</LoggedOnUser>
<DotNetFrameWork>4.0.30319.42000</DotNetFrameWork>
<ComputerName>TR-PUB</ComputerName>
<ConnectedToNetwork>True</ConnectedToNetwork>
<PhysicalMemory>4087036 MB</PhysicalMemory>
</Environment>
</SDLErrorDetails>

I restart my computer for several times, but this still can not be resolved.

Would you please tell me what I should do by referring the message above?

Thanks for your help in advance.

Thanks.