Private Sub FormLogin_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    txtLogin.Text = My.Settings.UserLogin.Trim()   ' в этой строке генерируется ошибка

'------------------------------------------------------------------------------
' <auto-generated>
'     Этот код создан программой.
'     Исполняемая версия:4.0.30319.1
'
'     Изменения в этом файле могут привести к неправильной работе и будут потеряны в случае
'     повторной генерации кода.
' </auto-generated>
'------------------------------------------------------------------------------

Option Strict On
Option Explicit On


Namespace My
    
    <Global.System.Runtime.CompilerServices.CompilerGeneratedAttribute(),  _
     Global.System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "10.0.0.0"),  _
     Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)>  _
    Partial Friend NotInheritable Class MySettings
        Inherits Global.System.Configuration.ApplicationSettingsBase
        
        Private Shared defaultInstance As MySettings = CType(Global.System.Configuration.ApplicationSettingsBase.Synchronized(New MySettings()),MySettings)
        
#Region "Функциональные возможности автосохранения My.Settings"
#If _MyType = "WindowsForms" Then
    Private Shared addedHandler As Boolean

    Private Shared addedHandlerLockObject As New Object

    <Global.System.Diagnostics.DebuggerNonUserCodeAttribute(), Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)> _
    Private Shared Sub AutoSaveSettings(ByVal sender As Global.System.Object, ByVal e As Global.System.EventArgs)
        If My.Application.SaveMySettingsOnExit Then
            My.Settings.Save()
        End If
    End Sub
#End If
#End Region
        
        Public Shared ReadOnly Property [Default]() As MySettings
            Get
                
#If _MyType = "WindowsForms" Then
               If Not addedHandler Then
                    SyncLock addedHandlerLockObject
                        If Not addedHandler Then
                            AddHandler My.Application.Shutdown, AddressOf AutoSaveSettings
                            addedHandler = True
                        End If
                    End SyncLock
                End If
#End If
                Return defaultInstance
            End Get
        End Property
        
        <Global.System.Configuration.ApplicationScopedSettingAttribute(),  _
         Global.System.Diagnostics.DebuggerNonUserCodeAttribute(),  _
         Global.System.Configuration.SpecialSettingAttribute(Global.System.Configuration.SpecialSetting.ConnectionString)>  _
        Public ReadOnly Property cnnString() As String
            Get
                Return CType(Me("cnnString"),String)
            End Get
        End Property
        
        <Global.System.Configuration.UserScopedSettingAttribute(),  _
         Global.System.Diagnostics.DebuggerNonUserCodeAttribute(),  _
         Global.System.Configuration.DefaultSettingValueAttribute("_ИМЯ_ПОЛЬЗОВАТЕЛЯ_")>  _
        Public Property UserLogin() As String
            Get
                Return CType(Me("UserLogin"),String)   'отладчик указывает на эту строку
            End Get
            Set
                Me("UserLogin") = value
            End Set
        End Property
    End Class
End Namespace

Namespace My
    
    <Global.Microsoft.VisualBasic.HideModuleNameAttribute(),  _
     Global.System.Diagnostics.DebuggerNonUserCodeAttribute(),  _
     Global.System.Runtime.CompilerServices.CompilerGeneratedAttribute()>  _
    Friend Module MySettingsProperty
        
        <Global.System.ComponentModel.Design.HelpKeywordAttribute("My.Settings")>  _
        Friend ReadOnly Property Settings() As Global.CashDesk.My.MySettings
            Get
                Return Global.CashDesk.My.MySettings.Default
            End Get
        End Property
    End Module
End Namespace

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <configSections>
        <sectionGroup name="userSettings" type="System.Configuration.UserSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
            <section name="CashDesk.My.MySettings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" allowExeDefinition="MachineToLocalUser" requirePermission="false" />
        </sectionGroup>
    </configSections>
    <startup>
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0,Profile=Client" />
    </startup>
    <userSettings>
        <CashDesk.My.MySettings>
            <setting name="UserLogin" serializeAs="String">
                <value>_ИМЯ_ПОЛЬЗОВАТЕЛЯ_</value>
            </setting>
        </CashDesk.My.MySettings>
    </userSettings>
</configuration>