Firebird reading database issue on iis asp.net core 5

Question

I want to develop a demo project in ASP.NET Core MVC with embedded Firebird v2.5. I read Firebird connection string information from a text file. Because I will change database in project presentation thus I must read from a text file. Or what is the your idea?

In this project I create a DbContext file and I fill in the database information using this class:

public class DbContext
{
    string startupdirectory = Path.GetDirectoryName(System.Reflection.Assembly.GetEntryAssembly().Location)+"\\settings.txt";
    string dblocation = string.Empty;
    string userName = string.Empty;
    string pass = string.Empty;
    int port = 0;
    string dataSource = string.Empty;
   
    public DbContext()
    {
        if (File.Exists(startupdirectory))
        {
            string[] allData = File.ReadAllLines(startupdirectory);
            dblocation = allData[0].ToString();
            userName = allData[1].ToString();
            pass = allData[2].ToString();
            port = Convert.ToInt32(allData[3].ToString());
            dataSource = allData[4].ToString();
        }
    }

    public string GetConnectionString()
    {
        FbConnectionStringBuilder csb = new();
        csb.Database = dblocation;
        csb.DataSource = dataSource;
        csb.UserID = userName;
        csb.Password = pass;
        csb.ServerType = FbServerType.Default;
        csb.Port = port;
        //i added below code for embedded db
        csb.Dialect = 3;
        csb.Role = "";
        csb.ConnectionLifeTime = 15;
        csb.Pooling = true;
        csb.MinPoolSize = 0;
        csb.MaxPoolSize = 50;
        csb.PacketSize = 8192;
        return csb.ToString();
    }

    public FbConnection GetConnection()
    {
        string connectionString = GetConnectionString();
        FbConnection connection = new();
        connection.ConnectionString = connectionString;
        connection.Open();
        return connection;
    }

    public void KillConnection(FbConnection connection)
    {
        connection.Close();
        connection.Dispose();
    }
}

When I work locally, everything is fine. I can do all CRUD operations.

But when I upload my project, I see this screen:

An unhandled exception occurred while processing the request.

IscException: I/O error during "CreateFile (open)" operation for file "C:\Firma\BlinePalmeWEB\Mandanten\11PalmeIT\GDI21.FDB"

Error while trying to open file

FirebirdSql.Data.Client.Managed.GdsConnection.HandleResponseException(IResponse response)

FbException: I/O error during "CreateFile (open)" operation for file "C:\Firma\BlinePalmeWEB\Mandanten\11PalmeIT\GDI21.FDB"

Error while trying to open file
FirebirdSql.Data.FirebirdClient.FbConnectionInternal.Connect()

Stack Query Cookies Headers Routing

IscException: I/O error during "CreateFile (open)" operation for file "C:\Firma\BlinePalmeWEB\Mandanten\11PalmeIT\GDI21.FDB" Error while trying to open file FirebirdSql.Data.Client.Managed.GdsConnection.HandleResponseException(IResponse response) FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.ReadResponse() FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.Attach(DatabaseParameterBufferBase dpb, string database, byte[] cryptKey) FirebirdSql.Data.FirebirdClient.FbConnectionInternal.Connect()

Show raw exception details
FbException: I/O error during "CreateFile (open)" operation for file "C:\\Firma\\BlinePalmeWEB\\Mandanten\\11PalmeIT\\GDI21.FDB" Error while trying to open file
FirebirdSql.Data.FirebirdClient.FbConnectionInternal.Connect()
FirebirdSql.Data.FirebirdClient.FbConnection.Open()
GDIWebApplication.Controllers.DbContext.GetConnection() in DbContext.cs
GDIWebApplication.Models.Deneme.ProductRepository.GetArtikelList() in ProductRepository.cs
GDIWebApplication.Controllers.ProductController.Index(string search) in ProductController.cs
lambda_method1(Closure , object , object[] )
Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor+SyncActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, object controller, object[] arguments)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeActionMethodAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeNextActionFilterAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, object state, bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

Show raw exception details
FirebirdSql.Data.FirebirdClient.FbException (0x80004005): I/O error during "CreateFile (open)" operation for file "C:\\Firma\\BlinePalmeWEB\\Mandanten\\11PalmeIT\\GDI21.FDB"
Error while trying to open file
 ---> FirebirdSql.Data.Common.IscException: I/O error during "CreateFile (open)" operation for file "C:\\Firma\\BlinePalmeWEB\\Mandanten\\11PalmeIT\\GDI21.FDB"
Error while trying to open file
   at FirebirdSql.Data.Client.Managed.GdsConnection.HandleResponseException(IResponse response)
   at FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.ReadResponse()
   at FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.Attach(DatabaseParameterBufferBase dpb, String database, Byte[] cryptKey)
   at FirebirdSql.Data.FirebirdClient.FbConnectionInternal.Connect()
   at FirebirdSql.Data.FirebirdClient.FbConnectionInternal.Connect()
   at FirebirdSql.Data.FirebirdClient.FbConnection.Open()
   at GDIWebApplication.Controllers.DbContext.GetConnection() in C:\Users\MD\source\repos\GDIWebApplication\Models\Context\DbContext.cs:line 60
   at GDIWebApplication.Models.Deneme.ProductRepository.GetArtikelList() in C:\Users\MD\source\repos\GDIWebApplication\Models\Repositories\ProductRepository.cs:line 20
   at GDIWebApplication.Controllers.ProductController.Index(String search) in C:\Users\MD\source\repos\GDIWebApplication\Controllers\ProductController.cs:line 16
   at lambda_method1(Closure , Object , Object[] )
   at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.SyncActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeActionMethodAsync()
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeNextActionFilterAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
   at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

I added all privileges is IIS but I can't make this work - how can I solve this?