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I'm a starter in OpenCV. My programming environment is VC++ Express 2010 + OpenCV 2.4.2 + Win 7 64 bit.

I use purely 32bit configuration in my VC++ and Path.

I type in the following code:

#include "opencv2\highgui\highgui.hpp"
#include "opencv2\core\core.hpp"
using namespace cv;
int main(int argc, char** argv) {
    char* imgPath = "logo.png";
    Mat img = imread(imgPath);
    namedWindow( "Example1", WINDOW_AUTOSIZE);
    imshow("Example1", img);
    waitKey(0);
    return 0;
Then I compile and run. It does come up with a window (but without picture) but then gave me this (a runtime error?)
Unhandled exception at 0x770515de in Helloworld2.exe: Microsoft C++ exception: cv::Exception at memory location 0x001ef038..
Then I change the imread into cvLoadImage and it works without any errors.
Can someone tell me what's wrong?
I have tried the code you have given. It works perfectly fine with my installation of OpenCV.
However I am getting a warning at the line:
char* imgPath = "logo.png";
main.cpp:6:21: warning: deprecated conversion from string constant to 'char*' [-
Wwrite-strings]
Which i think is nothing serious to make the code crash, however it might be the problem in your case, as I am not using VC++ to compile.
What you can try to check if this is the issue is to replace imgPath with directly the string, so the code will now be like
Mat img = imread("logo.png"); 
I also got this issue, but I fixed it with the following. The point is using absolute path other than relative path, and change "\" with "/" in the file path.
#include <opencv2\core\core.hpp>
#include <opencv2\highgui\highgui.hpp>
int main() {
    cv::Mat image = cv::imread("D:/projects/test/Debug/1.jpg");
    if (image.empty()) {
        return 0;
    cv::namedWindow("my image");
    cv::imshow("my image", image);
    cv::waitKey(5000);
    return 1;
But there is an implicit conversion from const char * to string. As masad noted, this conversion is deprecated, so it is very compiler dependent.
As cvLoadImage works for you, it seems that you should change your code to something like this:
#include "opencv2\highgui\highgui.hpp"
#include "opencv2\core\core.hpp"
#include <string>
using namespace cv;
int main(int argc, char** argv) {
    std::string imgPath("logo.png");
    Mat img = imread(imgPath);
    namedWindow( "Example1", WINDOW_AUTOSIZE);
    imshow("Example1", img);
    waitKey(0);
    return 0;
There has been some problems with C++ interface in Visual Studio, but you may try to see if it works for you.
I had the same problem and I came across Installing OpenCV 2.4.3 in Visual C++ 2010 Express and it mentions to use the updated set of libraries *d.lib when adding dependencies for the Linker. I tried it and the C++ interface worked. Not sure if this is the case in general. I am using OpenCV 2.4 and Visual Studio 2010 on a 64 bit Windows machine. 
I got the similar problem with you. When I use the imread function, the program crash with system error message:
opencv_debug.exe 中的 0x0036299f 处未处理的异常: 0xC0000005: 读取位置 0xcccccccc 时发生访问冲突
Then I change the imread into cvLoadImage and it works without any errors.
Finally, I fix the problem, it comes because I used VS2008 project with VS2010 compiled dll.
Here is my story.
Environment: VS2008 + opencv2.4.7
First, I just follow the link http://docs.opencv.org/doc/tutorials/introduction/windows_visual_studio_Opencv/windows_visual_studio_Opencv.html, and compile the my test project.
But, When I run my test project, the system error dialog tells me that I lost MSVCP100D.dll MSVCR100D.dll. So I download the two dll, the dll lost problem is solved, but the problem is crash on run time.
Notice that ahead link, it says:
it means that, in opencv2.4.7, they only provide dlls which compiled in vs2010 or vs2012, not vs2008.
When I compiling vs2008 project with dlls which compiled by vs2010, I get the wired problem.
How can I fix this problem?
use the older opencv version such as opencv2.3, this version contains the vs2008 compiled dll.
compile the opencv by yourself.
I have noticed that your environment is: VC++ Express 2010 + OpenCV 2.4.2 + Win 7 64 bit. 
Be sure OPENCV_DIR is set right.
setx -m OPENCV_DIR D:\OpenCV\Build\x64\vc10
        
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