DHCP Failed. APIPA is being used.

[Rupert Smith]

I am working on an assignment for a college course and I am having trouble getting my DHCP settings to work properly. The goal of the assignment is to break up the devices on the Main-Office-Router so that each department is on its own VLAN. I did this (I think) and now the DHCP does not work. I think it is because the servers got close off under VLAN 20, but I am not sure if there is a way around that.

Here are the steps I am expected to complete. Any direction you can provide is appreciated.

Steps: 

1. Review all VLANs and trunking. Previously, we allowed all VLANs to cross all trunks; this will no longer be the case.
2. Only allow VLAN 20, the server farm VLAN, to access Switch-03
3. Only VLAN 1, the Admin VLAN, should be allowed on Switch-02. Modify the trunk port configuration, similar to step 3, to do this. To test that it works, try to ping from the Engineering workstation on Switch-02. It should fail.
4. All other workstations on Switch-02 are to be moved to Switch-01, with Engineering moved to a new switch, Switch-04 on the port where one of the Engineering workstations was before. Only the Engineering VLAN will be allowed to Switch-04. This is similar to step 3. Make sure the Engineering PCs can obtain an address by DHCP and can ping out.
5. Restrict the remote locations [1 and 2] to their respective VLANS.

I attached my starting file (T1AddLocations) and my current progress (T2LimitVLANs). My current progress is filled with various troubleshooting methods so it may be a little messy at the moment. That is why I attached the starting file as well. Thanks in advance, I appreciate it.

[Kasun Bandara]

i checked  second attachment. 

1. make sure your DHCP server can access by intermediate routers. configure server connected switch ports access and vlan 20. 2.  switch 3 to switch 1 link needs to be trunk and allow required vlans. (for server 20).
3. add ip helper addresses in main office router serial interfaces correctly.
4. check if server pingable from branch routers
5. do dhcp check again

note - i saw in branch router 1, help address is wrong.

apply this sequence for all branch routers