Entity Framework errors: An error occurred while updating the entries.

Multiple situation where Entity Framework was giving me problem while adding new record, updating record or deleting.  Then here are few things which may go wrong:


Solution 1. Check whether Database Table has Proper primary key setup.

Solution 2. Check your DB table and POCO Model class is in sync.  If you have some extra properties which you have to use in POCO class but doesn't need in DB Table, then you may create [Not Mapped] Property.
Example:

 [NotMapped]
 public bool IsEditMode { get; set; }

Solution 3. Are you assigning date column a default value of DateTime.MinValue before add or update operation?  If yes, then this may also result into this problem.

Solution 4. Check if you have any decimal field in your table?  If yes then you will need to make proper configuration changes OnModelCreating.  In order to do so, add following code inside: OnModelCreating method inside your DBContext file.

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
//Precision and scale should match sql server table decimal field.
modelBuilder.Entity().Property(x => x.YOUR_DECIMAL_FIELDNAME).HasPrecision(26, 16);
}


This error could be sometime tricky since this may occur due to many reasons, so if you run into any other situation and found the solution, Please add your comment here.

Hope this will help to narrow down your problem.