Hi,
From the log you have sent I can see that the error starts with:
"08/03/2014 14:01:59 vuser_init.c(191): Error: DEBUG: Error in Login: TimeStamp=2014-03-08 14:01:59.461, User=xtra-3-3.xtraall@thomsonreuters.com, Env=PPE_INET [MsgId: MERR-17999]"
It is difficult to say what the issue is without having the VuGen script replayed with full extended mode and the raw results from the test.
You can start with analyze what happens at the failing step in the VuGen script which is used for the failing Vuser.
The log shows that it is located in the vuser_init section on line 191. You can check if something in the step could cause the error message for example is there a time stamp the step relies on during replay, or in case parameterization is used, are there enough parameters available, is the correct parameter used etc.
Kind regards,