Let's divide up the issues here
Problem #1: The DIP Switches
SW1
===
switches 1-6 equals Rack #4 which is invalid. Your G File Config specifies Rack #0. Change SW1-4 to On to configure the remote chassis as Rack #0
switches 7 & 8 You have this configured so that your starting I/O Group # is 6. You will want set to be group #0. Change these switch position to ON (for both).
SW2
===
switches 1 & 2 configure Baud Rate. Yours is currently set for 57.6Kb. This is a good starting point. Do not change unless it is determined you need faster update speed.
switch 3 must be off. This is a setting for complimentary mode which you are not using. Change this switch.
switch 4 must be ON. Do not change.
switches 5-8 set the rack size. You have your system configured to transfer 4 I/O groups worth of data. This setting will in part be determined by how you set the Addressing Mode via SW3 switches 5 & 6. You have those set for 2-slot addressing. Based on the way you have these modules arranged in the Remote chassis, 2-slot addressing is acceptable. However be aware that any empty slots after slot #8 would be unusable. You might consider changing this setting from 4 I/O groups to 6. I will proceed though assuming 4 I/O groups. So the current setting for these switches is acceptable.
SW3
===
switch 1 is set to Not Hold Last State. This is acceptable. Do not change.
switch 2 enables automatic restart of the adapter by the processor. You have this option enabled. Do not change.
switch 3 is an option to operate with unrestricted response times. This option should be set to the ON "Restricted" position unless your network experiences time out issues. Change this back to the default ON position.
switch 4 identifies if this chassis is the last chassis on the physical network. You have it in the default "Not Last Chassis" setting. This is acceptable. Do not change.
switch 5 & 6 configure the Addressing Mode. You are configured for 2-slot addressing. Based on the layout of your I/O modules this is acceptable. Do not change.
switch 7 determines whether Discrete or Block Transfer mode is used. The modules you are using ignore this setting. This is primarly for analog and other "smart" modules communicate. Do not change.
switch 8 determines if the adapter is to check the modules identify or save the modules identity. You have it set to SAVE. This is acceptable. Do not change.
Problem #2: The G File Configuration
This setting needs to be changed from Logical Rack 0 as a FULL RACK to 1/2 RACK. This correspondes to the correctitons in DIP switches listed above. Basically you had told the adapter module that it was at Rack #4 (invalid) starting with Group #6 and that it had four groups. Which would have meant your four I/O Groups would have been Rack 4 Group 6, Rack 4 Group 7, Rack 5 Group 0 and Rack 5 Group 1. However the G File was telling the scanner module (1747-SN) to go look for eight I/O Groups starting at Rack 0 Group 0 through Rack 0 Group 7. The scanner couldn't "find" the adapter.
Problem #3: The Ladder Logic Block Transfers
Erase it all. Block Transfers are only used if Block Transfer Mode was selected (SW3-7) which you are not. Block Transfers are only used for the analog and some other "smart" modules. The Discrete modules you are using cannot use Block Transfers. Their data will automatically be transferred (discretely). No logic is required for this to happen.
So, let us know what happens!
OG