ConvertId operation

Find information about the ConvertId EWS operation.

The ConvertId Exchange Web Services (EWS) operation converts item and folder identifiers between formats that are accepted by Exchange Online, Exchange Online as part of Office 365, and on-premises versions of Exchange starting with Exchange Server 2013.

Using the ConvertId operation

You can convert the following identifiers by using the ConvertId operation:

• The identifier format for EWS in the initial release version of Exchange 2007. This is represented by the EwsLegacyId enumeration value in the IdFormat enumeration.

• The identifier format for EWS in Exchange 2007 SP1 or Exchange 2010. This is represented by the EwsId enumeration value in IdFormat.

• The MAPI identifier, as in the PR_ENTRYID property. This is represented by the EntryId enumeration value in the IdFormat enumeration.

• The availability calendar event identifier. This is a hexadecimal-encoded representation of the PR_ENTRYID property. This is represented by the HexEntryId enumeration value in IdFormat.

• The Exchange store identifier. This is represented by the StoreId enumeration value in IdFormat. The ConvertId operation does not convert public folder identifiers from the EWS identifier to the store identifier.

• The Outlook Web App identifier. This is represented by the OwaId enumeration value in IdFormat

  The passing of URLs that are created from this identifier to Outlook Web App is not supported. The Outlook Web App identifier is applicable to Exchange 2007 and Exchange 2010. Outlook Web App for Exchange Online and versions of Exchange starting with Exchange Server 2013 uses EWS identifiers.

The ConvertId operation does not work as expected when converting public folder identifiers from the EWS identifier to the store identifier in Exchange Online and Exchange 2013. You can manually update the identifier that is returned as a workaround. To manually update the identifier:

1. In your application code, determine whether the target item/folder is in a public folder.

2. Decode the Base64-encoded identifier string.

3. Verify that the type byte (21st byte) has a value of 7. A value of 7 indicates that the identifier is in the incorrect format.

4. Skip the first four bytes. They must be set to zero.

5. Update the next 16 bytes with the following GUID: 1A447390AA6611CD9BC800AA002FC45A

6. Update the next byte (type byte) with a value of 9.

7. Change the identifier to a Base64-encoded string.

The ConvertId operation can use the SOAP headers that are listed in the following table.

Table 1. ConvertId operation SOAP headers

ConvertId operation request example

The following example of a ConvertId request shows how to convert from an EWS identifier to an Outlook Web App identifier.

The RequestServerVersion element in the SOAP header must be set to Exchange2007_SP1 or later for this operation to work.

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
               xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
  <soap:Header>
    <t:RequestServerVersion Version="Exchange2010"/>
  </soap:Header>
  <soap:Body>
    <ConvertId xmlns="http://schemas.microsoft.com/exchange/services/2006/messages"
               xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
               DestinationFormat="OwaId">
      <SourceIds>
        <t:AlternateId Format="EwsId" Id="AAMkAGZhN2IxYTA0LWNiNzItN="
                       Mailbox="user1@example.com"/>
      </SourceIds>
    </ConvertId>
  </soap:Body>
</soap:Envelope>

ConvertId operation response example

The following example shows a successful response to a ConvertId request. This response example contains an Outlook Web App identifier.

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" 
               xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
               xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <soap:Header>
    <t:ServerVersionInfo MajorVersion="8" MinorVersion="1" 
                         MajorBuildNumber="191" MinorBuildNumber="0" 
                         Version="Exchange2010" 
                         xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types" />
  </soap:Header>
  <soap:Body>
    <ConvertIdResponse xmlns="http://schemas.microsoft.com/exchange/services/2006/messages">
      <ResponseMessages>
        <ConvertIdResponseMessage ResponseClass="Success">
          <ResponseCode>NoError</ResponseCode>
          <AlternateId xsi:type="t:AlternateIdType" Format="OwaId" Id="RgAAAAAS2%2" 
                         Mailbox="user@example.com" />
        </ConvertIdResponseMessage>
      </ResponseMessages>
    </ConvertIdResponse>
  </soap:Body>
</soap:Envelope>

ConvertId operation error response example

The following example shows the response to a request that contains the wrong type of identifier format.

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
               xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
               xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <soap:Header>
    <ServerVersionInfo MajorVersion="8" MinorVersion="1" 
                       MajorBuildNumber="206" MinorBuildNumber="0"
                       Version="Exchange2010" 
                       xmlns="http://schemas.microsoft.com/exchange/services/2006/types" />
  </soap:Header>
  <soap:Body>
    <ConvertIdResponse xmlns="http://schemas.microsoft.com/exchange/services/2006/messages">
      <ResponseMessages>
        <ConvertIdResponseMessage ResponseClass="Error">
          <MessageText>Id is malformed.</MessageText>
          <ResponseCode>ErrorInvalidIdMalformed</ResponseCode>
          <DescriptiveLinkKey>0</DescriptiveLinkKey>
        </ConvertIdResponseMessage>
      </ResponseMessages>
    </ConvertIdResponse>
  </soap:Body>
</soap:Envelope>

Version differences

The EWS identifier format changed between the initial release version of Exchange 2007 and Exchange 2007 Service Pack 1 (SP1). Exchange Online as part of Office 365, Exchange Online, and on-premises versions of Exchange starting with Exchange 2010 use the same identifier format that Exchange 2007 SP1 uses.

The ConvertId operation converts public folder identifiers from the EWS identifier to the store identifier in Exchange 2007 and Exchange 2010.

See also

• Converting Identifiers

• ConvertIdType

• ConvertId