Symptoms
When you are running an Advanced Program-to-Program Communications (APPC) or Common Programming Interface for Communications (CPI-C) application, you may encounter an Access Violation (AV) in DMODInitReceiveAllocate.
If Dr. Watson is configured as the default debugger, an entry similar to the following may be appended to the Drwtsn32.log file:

function: DMODInitReceiveAlloc6721a1c4 8d54d034leaedx,[eax+edx*8+0x34]ds:040cbeef=????????6721a1c8 83c9fforecx,0xff6721a1cb 33c0xoreax,eax6721a1cd f2aerepnescasbes:02ced4e8=??6721a1cf f7d1notecx6721a1d1 2bf9subedi,ecx6721a1d3 8bc1moveax,ecx6721a1d5 8bf7movesi,edi6721a1d7 8bfamovedi,edx6721a1d9 c1e902shrecx,0×2FAULT ->6721a1dc f3a5repmovsd ds:0284f79c=20202020 es:02ced4e8=????????6721a1de 8bc8movecx,eax6721a1e0 83e103andecx,0×36721a1e3 f3a4repmovsbds:0284f79c=20 es:02ced4e8=??6721a1e5 33c0xoreax,eax6721a1e7 8b7dc4movedi,[ebp-0x3c]ss:03c2e26e=????????6721a1ea 668b4704movax,[edi+0x4]ds:040cbeef=????6721a1ee 8d0c40leaecx,[eax+eax*2]ds:0000001b=????????6721a1f1 c1e103shlecx,0×36721a1f4 2bc8subecx,eax6721a1f6 8bb548ffffffmovesi,[ebp+0xffffff48]ss:0284f7b0=02cc025c6721a1fc c744ce1004000000ds:013dea0d=????????movdword ptr [esi+ecx*8+0x10],0×4*—-> Stack Back Trace <—-*FramePtr ReturnAd Param#1Param#2Param#3Param#4Function Name0284f868 63404de3 62e1b5b0 00000001 00a9a4bc 00a9a4d8 snadmod!DMODInitReceiveAlloc (FPO: Non-FPO [5,128,3])0284f89c 63403254 00000000 63401bb6 0284fa0c 0f7e0000 wappc32!receive_allocate_proc(FPO: [EBP 0x00014000] [0,3,4])0284f8a4 63401bb6 0284fa0c 0f7e0000 00000000 77f674c0 wappc32!ps_verb_router(FPO: [0,0,1])0284f9bc 63401737 0f7e0000 00000002 62e018a0 00000000 wappc32!Appc_Main(FPO: [EBP 0x0284fa0c] [4,65,4])
Resolution
The application exception is caused by a buffer overrun during Dynamic Load processing.