I have a S4 4.2 V8 ECU    8E2 910 560F .     I read the original with a programmer and wrote a sai off file.     after 1 week I changed the file and now car wont run.    Tried to read via bench with no luck.   I wrote back original file on flash chip and car still wont start or communicate.     

When I read ECU info I get
0x94, System Supplier ECU Software Number: 0x0000,
   0x91, Vehicle Manufacturer ECU Hardware Number: 0x0D, 8E2907560   , 0xFF,
   0x9B, Calibration Date:  0x00001E22, 0x00000000, 0x0000,                ,      ,
   0x9C, Calibration Equiment Software Number: 0x02000000,

If I try to read with the ecu on the bench harness I get
Disabling Windows sleep mode.
Reading ECU flash memory.
ECU reports programming session preconditions have been met.
Negotiating communication timings.
Timing negotiation failed. Communication timings are unchanged.
Requesting security access.
Security access granted.
Starting diagnostic session.
Successfully started diagnostic session.
Negotiating communication timings.
Successfully changed to new communication timings.
Requesting security access.
Security access granted.
Validating flash memory starts at 0x00800000 and ends at 0x00900000.
Validation failed, ECU reports RequestUpload service is not supported. RequestUpload may have been disabled by aftermarket engine software.
Memory layout validation failed.
Starting to read data block.
Calculating flash checksum to determine if reading is necessary for range: 0x00800000 to 0x00804000
Checksum validation routine did not start or complete correctly.
Flash checksum does not match, reading flash data is necessary.
Requesting upload from ECU for address range 0x00800000 to 0x00803FFF.
Request upload from ECU failed, ECU reports service is not supported. Request upload may have been disabled by aftermarket engine software.
Reading ECU flash memory failed. Trying to force ECU to recognize read operation is complete.
Checksum validation routine did not start or complete correctly.
Finished forcing ECU to recognize that failed read operation is complete.
Reading ECU flash memory failed.
100% complete.
Restoring Windows sleep mode.

Anyone have anything I can try?

pin 21 has power.   VCDS shows a bunch of blank info or 0000000

Change flash chip for new and flash standard file on it