Everytime I open the database from visual studio 2017 and then try to rebuild the solution of windows form I get those errors:

> 
> Severity Code Description Project File Line Suppression State
>  Error MSB3021 Unable to copy file "C:\Users\bsuro\documents\visual studio 2017\Projects\WindowsFormsApp2\WindowsFormsApp2\App\_Data\Database.mdf" to "bin\Debug\App\_Data\Database.mdf". The process cannot access the file 'C:\Users\bsuro\documents\visual studio 2017\Projects\WindowsFormsApp2\WindowsFormsApp2\App\_Data\Database.mdf' because it is being used by another process. C:\Users\bsuro\documents\visual studio 2017\Projects\WindowsFormsApp2\WindowsFormsApp2\WindowsFormsApp2.csproj C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\MSBuild\15.0\Bin\Microsoft.Common.CurrentVersion.targets 4353 
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> 
> Severity Code Description Project File Line Suppression State
>  Error MSB3027 Could not copy "C:\Users\bsuro\documents\visual studio 2017\Projects\WindowsFormsApp2\WindowsFormsApp2\App\_Data\Database.mdf" to "bin\Debug\App\_Data\Database.mdf". Exceeded retry count of 10. Failed. C:\Users\bsuro\documents\visual studio 2017\Projects\WindowsFormsApp2\WindowsFormsApp2\WindowsFormsApp2.csproj C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\MSBuild\15.0\Bin\Microsoft.Common.CurrentVersion.targets 4353 
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How can I fix it?