Gen partner delivered their Gen 8.6 application and runtimes to customer who encountered error:
TIRM030E: Application failed - Updates have been backed out
CSU-DLL-ERROR: (Sys-126) Attach to tcpcfn.dll failed in function CSUWin32Library::attach.
Release: 8.6
Component: Gen Runtime Distributed
PTF maintenance level
After installing PTFs RTN86217/LU03130 and RTN86220/LU04696, the problem was resolved.
The Gen partner also experienced the same error. They found that the problem was due to the fact that the tcpcfn.dll file from RTN86220/LU04696 had been installed but the PTF itself had not been fully installed and the required new dlls libcrypto-1_1.dll and libssl-1_1.dll from the PTF were missing.
NOTE: Recent Gen 8.6.3 Consolidation PTF WKS86300/LU06327 replaces both the above PTFs