Error during startup after converting application from VC++ -> Qt Creator

I had an application, written in Visual C++. I want to continue development using Qt Creator. My application now compiles successfully with Qt Creator, but when application launches (under debugger), it immediately exits with message "During startup program exited with code 0x0000c135".

I made following steps:
- Export .pri from VC++
- Rename .pri to .pro and open it in Qt Creator
- After fixing some settings regarding external libraries application now compiles and links successfully
- But I get error when starting application as mentioned above

Any hint what to do, please?

That sounds like a windows program error code. It could be that the debugger itself doesn't start properly.

Even if I start program without debugger, it immediately exits with no error message, Qt Creator application output shows "... exited with code -1073741515". I think this is the same error code?

No it's a different one. It probably means some Qt dll couldn't be found (creator sets the correct path for you). Put a breakpoint somewhere (in main()) to find out whether your program starts at all.

anyone here can pls help me with this error,
Could not find make command: make in the build environment
Error while building project TextFinder (target: Desktop)
When executing build step 'Make'pls reply soon of how to get rid of this error?

You do not give us enough data, like operating system, are u using Qt Creator and so on... But it looks like something is wrong with your Qt binaries path.