APPEND could not retrieve literal argument Error

Error​

APPEND could not retrieve literal argument.

Cause

This error is caused by a well-known bug in the IMAP implementation used by your email server. This typically affects IMAP servers known as SmarterMail.

MigrationWiz attempts to create items at the Destination as fast as possible and leverages IMAP fast create mode to maximize throughput.

In fast create mode, MigrationWiz pipelines item creation commands to provide significant speedup. Most systems support this mode of operation, but not all.

Resolution

• Upgrade Your IMAP Server
  Consider upgrading your IMAP server to a newer version with improved handling of IMAP Fast Create mode.
• Disable Fast Create mode
  If your IMAP server cannot be upgraded, the following workaround can be used:
  1. From the MSPComplete dashboard, click on All Products.
  2. From the overall project list, select your project  OR  select your customer from the All Customers drop-down list, then select your project.
  3. On the MigrationWiz project dashboard, click on Edit Project.
  4. Under Support > Support only options, enter MustWaitAfterLiteral=1.
  5. Click on Save.