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IEWSClient class provides feature to restore PST messages to exchange server. Following sample code demonstrates this feature where all the folders and respective messages are copied from PST to the mail box on Exchange server.
const string mailboxUri = “https://exchange.domain.com/ews/Exchange.asmx”;
const string domain = @"";
const string username = @“userName”;
const string password = @“password”;
NetworkCredential credentials = new NetworkCredential(username, password, domain);
IEWSClient client = EWSClient.GetEWSClient(mailboxUri, credentials);
string inputPst = @“Source.pst”;
Could you please give a try to the sample code and let us know your feedback?