These errors are referring to a riser missing or they aren't in the right slots. The riser with the single PCIe slot will go in the center slot on the motherboard? Also, is the other riser a PCIe or PCI-X riser? Lastly, do you have another system we can test the risers with?
  The following errors E1A11 Pci Rsr Config and  E1A12 Pc Rsr Missing is usually displayed on the LCD, and server can not be switched on. Expansion card raisers had been checked and repositioned just in case, but error had remained on E1A11. The E1A12  error code appears intermittently. Please any assistance will be very much appreciated. Thank you.
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