This is the error message I get when trying to "attach" the .mdf Hopefully this might help
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Failed to retrieve data for this request. (Microsoft.SqlServer.Management.Sdk.Sfc)
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For help, click: https://go.microsoft.com/fwlink?ProdName=Microsoft%20SQL%20Server&LinkId=20476
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Program Location:
at Microsoft.SqlServer.Management.Sdk.Sfc.Enumerator.Process(Object connectionInfo, Request request)
at Microsoft.SqlServer.Management.SqlManagerUI.AttachDatabaseData.PrimaryFile.GetOriginalDatabaseName(String primaryFilePath)
at Microsoft.SqlServer.Management.SqlManagerUI.AttachDatabaseData.PrimaryFile.PopulatePrimaryFileData(String primaryFilePath, Boolean isXIPath)
at Microsoft.SqlServer.Management.SqlManagerUI.AttachDatabaseData.PrimaryFile..ctor(SqlManagementUserControl parent, CDataContainer dc, String fullPath, String databaseOwner, ServerConnection connectionInfo, Boolean isXIPath)
at Microsoft.SqlServer.Management.SqlManagerUI.AttachDatabase.AddPrimaryFile(String fullPath, String fileName, Boolean isXIPath)
at Microsoft.SqlServer.Management.SqlManagerUI.AttachDatabase.buttonBrowse_Click(Object sender, EventArgs e)
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An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)
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Program Location:
at Microsoft.SqlServer.Management.Common.ServerConnection.GetExecuteReader(SqlCommand command)
at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteReader(String sqlCommand, SqlCommand& command)
at Microsoft.SqlServer.Management.Smo.ExecuteSql.GetDataReader(String query, SqlCommand& command)
at Microsoft.SqlServer.Management.Smo.DataProvider.SetConnectionAndQuery(ExecuteSql execSql, String query)
at Microsoft.SqlServer.Management.Smo.ExecuteSql.GetDataProvider(StringCollection query, Object con, StatementBuilder sb, RetriveMode rm)
at Microsoft.SqlServer.Management.Smo.SqlObjectBase.FillData(ResultType resultType, StringCollection sql, Object connectionInfo, StatementBuilder sb)
at Microsoft.SqlServer.Management.Smo.SqlObjectBase.FillDataWithUseFailure(SqlEnumResult sqlresult, ResultType resultType)
at Microsoft.SqlServer.Management.Smo.SqlObjectBase.BuildResult(EnumResult result)
at Microsoft.SqlServer.Management.Smo.PrimaryFile.GetData(EnumResult erParent)
at Microsoft.SqlServer.Management.Sdk.Sfc.Environment.GetData()
at Microsoft.SqlServer.Management.Sdk.Sfc.Environment.GetData(Request req, Object ci)
at Microsoft.SqlServer.Management.Sdk.Sfc.Enumerator.GetData(Object connectionInfo, Request request)
at Microsoft.SqlServer.Management.Sdk.Sfc.Enumerator.Process(Object connectionInfo, Request request)
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CREATE FILE encountered operating system error 32(The process cannot access the file because it is being used by another process.) while attempting to open or create the physical file 'D:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\DATA\EMC.mdf'. (Framework Microsoft SqlClient Data Provider)
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For help, click: https://docs.microsoft.com/sql/relational-databases/errors-events/mssqlserver-5123-database-engine-error
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Server Name: EANDMCOMMCS
Error Number: 5123
Severity: 16
State: 20
Line Number: 1
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Program Location:
at Microsoft.SqlServer.Management.Common.ConnectionManager.ExecuteTSql(ExecuteTSqlAction action, Object execObject, DataSet fillDataSet, Boolean catchException)
at Microsoft.SqlServer.Management.Common.ServerConnection.GetExecuteReader(SqlCommand command)
