MapiLogon MAPI: 6 - Mapi Runtime Error., The logon did not succeed, either because one or more of the parameters to MAPILogonEx were invalid or because there were too many sessions open already
As the above error message suggests, the error can occur for two reasons.
1) If you encounter the above error during a Try-Script message then it is likely that the parameters you have specified in the function “MapiLogon” are incorrect. To ensure that you have specified the correct Profile as the first parameter in the function “MapiLogon("Exchange", null);” you should go to:
CONTROL PANEL | MAIL | SHOW PROFILES and verify that the profile name specified, matches the name you have specified in the function.
If you are unsure about whether a password is required then speak to your IT Administrators for further assistance.
2) If you are encountering the error under load conditions then it is likely that you are encountering a limitation with your mail server as SilkPerformer has no control over the maximum number of MAPI sessions which can be open from a single machine. Therefore you should consider the following advice from the Microsoft Knowledge Base which provides suggestions on how you can tweak your install of Exechange Server to allow more MAPI sessions to be opened: http://support.microsoft.com/kb/842022