Write-Error

Writes an object to the error stream.

Syntax

Write-Error
     [-Message] <string>
     [-Category <ErrorCategory>]
     [-ErrorId <string>]
     [-TargetObject <Object>]
     [-RecommendedAction <string>]
     [-CategoryActivity <string>]
     [-CategoryReason <string>]
     [-CategoryTargetName <string>]
     [-CategoryTargetType <string>]
     [<CommonParameters>]
Write-Error
     [-Exception] <Exception>
     [-Message <string>]
     [-Category <ErrorCategory>]
     [-ErrorId <string>]
     [-TargetObject <Object>]
     [-RecommendedAction <string>]
     [-CategoryActivity <string>]
     [-CategoryReason <string>]
     [-CategoryTargetName <string>]
     [-CategoryTargetType <string>]
     [<CommonParameters>]
Write-Error
     [-ErrorRecord] <ErrorRecord>
     [-RecommendedAction <string>]
     [-CategoryActivity <string>]
     [-CategoryReason <string>]
     [-CategoryTargetName <string>]
     [-CategoryTargetType <string>]
     [<CommonParameters>]

Description

The Write-Error cmdlet declares a non-terminating error. By default, errors are sent in the error stream to the host program to be displayed, along with output.

To write a non-terminating error, enter an error message string, an ErrorRecord object, or an Exception object. Use the other parameters of Write-Error to populate the error record.

Non-terminating errors write an error to the error stream, but they don't stop command processing. If a non-terminating error is declared on one item in a collection of input items, the command continues to process the other items in the collection.

To declare a terminating error, use the Throw keyword. For more information, see about_Throw.

Examples

Example 1: Write an error for RegistryKey object

Get-ChildItem | ForEach-Object {
    if ($_.GetType().ToString() -eq "Microsoft.Win32.RegistryKey")
    {
        Write-Error "Invalid object" -ErrorId B1 -TargetObject $_
    }
    else
    {
        $_
    }
}

This command declares a non-terminating error when the Get-ChildItem cmdlet returns a Microsoft.Win32.RegistryKey object, such as the objects in the HKLM: or HKCU: drives of the PowerShell Registry provider.

Example 2: Write an error message to the console

Write-Error "Access denied."

This command declares a non-terminating error and writes an "Access denied" error. The command uses the Message parameter to specify the message, but omits the optional Message parameter name.

Example 3: Write an error to the console and specify the category

Write-Error -Message "Error: Too many input values." -Category InvalidArgument

This command declares a non-terminating error and specifies an error category.

Example 4: Write an error using an Exception object

$E = [System.Exception]@{Source="Get-ParameterNames.ps1";HelpLink="https://go.microsoft.com/fwlink/?LinkID=113425"}
Write-Error -Exception $E -Message "Files not found. The $Files location doesn't contain any XML files."

This command uses an Exception object to declare a non-terminating error.

The first command uses a hash table to create the System.Exception object. It saves the exception object in the $E variable. You can use a hash table to create any object of a type that has a null constructor.

The second command uses the Write-Error cmdlet to declare a non-terminating error. The value of the Exception parameter is the Exception object in the $E variable.

Parameters

-Category

Specifies the category of the error. The default value is NotSpecified. The acceptable values for this parameter are:

  • NotSpecified
  • OpenError
  • CloseError
  • DeviceError
  • DeadlockDetected
  • InvalidArgument
  • InvalidData
  • InvalidOperation
  • InvalidResult
  • InvalidType
  • MetadataError
  • NotImplemented
  • NotInstalled
  • ObjectNotFound
  • OperationStopped
  • OperationTimeout
  • SyntaxError
  • ParserError
  • PermissionDenied
  • ResourceBusy
  • ResourceExists
  • ResourceUnavailable
  • ReadError
  • WriteError
  • FromStdErr
  • SecurityError
  • ProtocolError
  • ConnectionError
  • AuthenticationError
  • LimitsExceeded
  • QuotaExceeded
  • NotEnabled

For information about the error categories, see ErrorCategory Enumeration.

Type:ErrorCategory
Accepted values:NotSpecified, OpenError, CloseError, DeviceError, DeadlockDetected, InvalidArgument, InvalidData, InvalidOperation, InvalidResult, InvalidType, MetadataError, NotImplemented, NotInstalled, ObjectNotFound, OperationStopped, OperationTimeout, SyntaxError, ParserError, PermissionDenied, ResourceBusy, ResourceExists, ResourceUnavailable, ReadError, WriteError, FromStdErr, SecurityError, ProtocolError, ConnectionError, AuthenticationError, LimitsExceeded, QuotaExceeded, NotEnabled
Position:Named
Default value:NotSpecified
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-CategoryActivity

Specifies the action that caused the error.

Type:String
Aliases:Activity
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-CategoryReason

Specifies how or why the activity caused the error.

Type:String
Aliases:Reason
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-CategoryTargetName

Specifies the name of the object that was being processed when the error occurred.

Type:String
Aliases:TargetName
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-CategoryTargetType

Specifies the type of the object that was being processed when the error occurred.

Type:String
Aliases:TargetType
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-ErrorId

Specifies an ID string to identify the error. The string should be unique to the error.

Type:String
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-ErrorRecord

Specifies an error record object that represents the error. Use the properties of the object to describe the error.

To create an error record object, use the New-Object cmdlet or get an error record object from the array in the $Error automatic variable.

Type:ErrorRecord
Position:0
Default value:None
Required:True
Accept pipeline input:False
Accept wildcard characters:False

-Exception

Specifies an exception object that represents the error. Use the properties of the object to describe the error.

To create an exception object, use a hash table or use the New-Object cmdlet.

Type:Exception
Position:0
Default value:None
Required:True
Accept pipeline input:False
Accept wildcard characters:False

-Message

Specifies the message text of the error. If the text includes spaces or special characters, enclose it in quotation marks. You can also pipe a message string to Write-Error.

Type:String
Aliases:Msg
Position:0
Default value:None
Required:False
Accept pipeline input:True
Accept wildcard characters:False

-RecommendedAction

Specifies the action that the user should take to resolve or prevent the error.

Type:String
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-TargetObject

Specifies the object that was being processed when the error occurred. Enter the object, a variable that contains the object, or a command that gets the object.

Type:Object
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

Inputs

String

You can pipe a string that contains an error message to this cmdlet.

Outputs

None

This cmdlet returns no output. It only writes to the error message stream.

Notes

Write-Error doesn't change the value of the $? automatic variable, therefore it doesn't signal a terminating error condition. To signal a terminating error, use the $PSCmdlet.WriteError() method.