Error: There is no row at position 0




 HI, i am currently working on a project, when i run the program, there is an error. It says this  

  

System.IndexOutOfRangeException was unhandled by user code  

Message="There is no row at position 0."  

Source="System.Data"  

  

**StackTrace:**  

  

at System.Data.RBTree`1.GetNodeByIndex(Int32 userIndex)  

at System.Data.RBTree`1.get\_Item(Int32 index)  

at System.Data.DataRowCollection.get\_Item(Int32 index)  

  

...  

  

  

  

Please help....its urgent....
If I am not wrong, you are trying to read or loop through the rows from datatable. This error states that the datasource(DataTable) is not having any rows. To avoid this exception use this before you read or loop through datatable:  


```
if(dt.Rows.Count  > 0 ){
     //Do your stuff here.
}
```
  

  

  

--Amit
This error has to do with the XFree86 config file. I'm not sure about Mandrake, but in Windows it's at /etc/X11/XF86Config or /etc/X11/XF86Config-4



This file can be hand-edited or configured via a program such as Xconfigurator or xf86config (I think those are the names of the programs? if you have them installed)



What video card are you using? If you're using an Nvidia based card, go to the Linux section of [nvidia.com](http://nvidia.com/) and there is a detailed text file with everything you need to know about this file to get it to work. that error happens when there's no handle to close. i see you call the 'open()' and you're not getting an object reference error before closehandle(). check your memory.pointerwrite() function to make sure it's not doing a closehandle() prematurely. it sounds like you're calling closehandle() twice. A segmentation fault in this case probably means you accessed one of the arrays out of bounds. Start up a debugger and keep a watch on your indices. hi [@gianna.demetroulakos](/u/gianna.demetroulakos),

as mentioned by [@william.coulson](/u/william.coulson), the object reference not set to an instance of an object normally occurs when a variable is null.

run the code in the debug mode.

when the error occurs, check the variable which has a null value in locals tab.

warm regards,

ranjith u… i suspect that the resource\_exhausted message may have originated from a back-pressuring committer node ([code](https://github.com/digital-asset/daml/blob/926fb5997a795e7f80443a9a3ba7898b1568d158/ledger/participant-integration-api/src/main/scala/platform/apiserver/services/apisubmissionservice.scala#l155-l157)). if that’s the case, i believe the approach should be the same: change the configuration if you need and make sure to handle those errors with the appropriate retry strategy. hi daniel,

that error message indicates either a dodgey account code, incorrect queue for job size/time limits or exceeding number of jobs allowed.

you need to specify a valid account code. n02 is not a valid budget.

regards,

ros. `out` parameters in SQL Server are fun. You have to repeat yourself *everywhere*.


Specifically, here, you've forgotten to mention it in the parameter list when calling the stored proc. `dbo.InsertPhones @model, @out` should be `dbo.InsertPhones @model, @out out`. There may also be a way to omit the parameter list from this string and instruct SQL Server that you're giving it a stored procedure name, not arbitrary query text, but I'm not sure how you would do that specifically here (with an `SqlCommand` object, it would be via the `CommandType` property).


If you're using an `out` parameter, the `select` at the end of the stored procedure is unnecessary, but I assume that was an attempt at a fix. I have figured out this issue and so for anyone else with the same issue.

In Designer for your XDP make sure you have a subform as the entry for the table row, and make this subform "Repeat Subform for Each Data Item" I found the subform could not be within another subform for this option to be visible.

So after this you can assign the row to the subform and the elements to the elements within the subform and hopefully it'll work.




[View solution in original post](/t5/adobe-experience-manager-forms/dynamic-rows-in-a-table-issue-also-relates-to-having-elements/m-p/204725#M6246) I have now implemented the following solution.


As CodeNotFound pointed out in the comments, IdentityUser used to have a `Roles` property. This is no longer the case in .NET Core. This [comment/issue](https://github.com/aspnet/Identity/issues/1361#issuecomment-348863959) on GitHub seems to be the current solution for .Net Core. I have attempted to implemented it with the following code:


**ApplicationUser**



```
public class ApplicationUser : IdentityUser
{
    public ICollection<ApplicationUserRole> UserRoles { get; set; }
}

```

**ApplicationUserRole**



```
public class ApplicationUserRole : IdentityUserRole<string>
{
    public virtual ApplicationUser User { get; set; }
    public virtual ApplicationRole Role { get; set; }
}

```

**ApplicationRole**



```
public class ApplicationRole : IdentityRole
{
    public ICollection<ApplicationUserRole> UserRoles { get; set; }
}

```

**DBContext**



```
public class ApplicationDbContext
    : IdentityDbContext<ApplicationUser, ApplicationRole, string, IdentityUserClaim<string>,
    ApplicationUserRole, IdentityUserLogin<string>,
    IdentityRoleClaim<string>, IdentityUserToken<string>>
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);

        builder.Entity<ApplicationUserRole>(userRole =>
        {
            userRole.HasKey(ur => new { ur.UserId, ur.RoleId });

            userRole.HasOne(ur => ur.Role)
                .WithMany(r => r.UserRoles)
                .HasForeignKey(ur => ur.RoleId)
                .IsRequired();

            userRole.HasOne(ur => ur.User)
                .WithMany(r => r.UserRoles)
                .HasForeignKey(ur => ur.UserId)
                .IsRequired();
        });
    }
}

```

**Startup**



```
services.AddIdentity<ApplicationUser, ApplicationRole>(options => options.Stores.MaxLengthForKeys = 128)
            .AddEntityFrameworkStores<ApplicationDbContext>()
            .AddDefaultTokenProviders();

```

Finally, make sure when you're using it that you eagerly load the User's UserRoles, and then the UserRole's Role like so:



```
this.Users = userManager.Users.Include(u => u.UserRoles).ThenInclude(ur => ur.Role).ToList();

```

I had an issue where the `Role` property of each `UserRole` was null and this was resolved by adding in the `.ThenInclude(ur => ur.Role)` part.


Microsoft doc on multi-level eager loading: <https://docs.microsoft.com/en-us/ef/core/querying/related-data#including-multiple-levels> Hello,

 

 

We would like to inform you that decoding MCE errors is out of the scope of support for us. As a general recommendation based on the wording for the log, please check the memory modules installed and confirm if one of them has failed.
 
 
 
 
 
 
 
 
 

[View solution in original post](/t5/Server-Products/How-to-decode-MCE-errors/m-p/527769#M13599)