# Incompatible library versions (VS2010)

• Just moving up from 4.8.3 to 4.8.4. on Windows using VS 2010. Downloaded the binaries and installed without any problems. My program builds and runs OK in release, but although the debug version seems to build OK, when I stry to run it I get the following error:

Debug Error!
Program: C:\Dev\fed3\FedTerm2.exe
Module: 4.8.3
File: global\qglobal.cpp
Line: 2246
Cannot mix incompatible Qt library (version 0x40804) with this library (version 0x40803)

Has anyone got any idea what's going on, and how I can fix it?

Thanks in anticipation

alan

• Did you try a complete rebuild?
That should solve your problem. However, I thought that there is a compatibility between versions. At least the dlls.

• No, I haven't done a rebuild - I just pulled down the binaries. It takes quite a long time to do a rebuild :(

I've never had this problem before when I upgraded, I thought maybe other people have had the same problem...

If there's no faster fix, I guess I'll have to build all the binaries from scratch. Thanks for the comment :)

alan

• Sorry, I meant rebuild of your own application in debug mode.

• OK, thanks. I built Qt from the the source package, and that fixed it. Building Qt was surprisingly easy, although I was a bit learey at first because the instructions referred to VS2005...

Someone put a lot of work into making the Windows build easy. Nice work - thanks, guys!