Active Users didn't find in MAP Toolkit

Dear All,

Yesterday I ran MAP Toolkit in my network to get the hardware and software inventory that installed in users computers. After gathering the inventory I found that MAP tool didn't collect AD user information. The other thing is viewed insufficient data with following errors: connection time out, connection refuses, machine not found, RPC server unavailable.

Kindly guide how to get the AD user information and resolve the insufficient errors.

Thanks