We're using Exchange Web Services to set user signature in Outlook Web Access. It works great, we see the signature under Options>Settings and the "Automatically include my signature on messages I send" check box is checked. We also set this programmatically.
However, when the user creates a new e-mail message in OWA the signature does not show up. A work around for this is to go to Options>Setting, uncheck the "Automatically include my signature on messages I send" check box , Save, check the check box again and save.
The code we use to set the signature looks something like this:
Folder rootFolder;
UserConfiguration OWAConfig;
rootFolder = Folder.Bind(service, WellKnownFolderName.Root);
OWAConfig = UserConfiguration.Bind(service, "OWA.UserOptions",rootFolder.ParentFolderId, UserConfigurationProperties.All);
OWAConfig.Dictionary["signaturehtml"] = "Hello World";
OWAConfig.Dictionary["autoaddsignature"] = "True";
OWAConfig.Update();
Any idea how to get around this problem?