First case:
This problem occurs mostly because " environment variable path" is not set , although you may have checked the add <...>\opencv\bin to the system path entry during the installation process!
After installing the OpenCV, be sure to check if the C:\Program File\opencv\bin has been added to the environment variable path, and if not, set the environment variable method by adding the path: My Computer---Properties--advanced- > Environment variable->path->c:\programfile\opencv\bin(set according to the installation path of OpenCV on the current computer, if multiple paths are set, separated by semicolons), restart the computer.
Second case:
Sometimes the above settings are set, but there will be problems, and there will be "no Cxcore100.dll found", you need to C:\Program files\opencv\opencv\ A copy of all the. dll files under bin (here is relative path) to System32 can resolve the issue. This is how I solve the problem.
The third case:
For the second case, some will copy all the. dll files under C:\Program files\opencv\opencv\bin to debug to resolve the problem. But in the second case when this problem occurs on my computer, the problem is solved.
Cxcore100.dll was not found, so this application failed to start and reinstalling the application may fix the problem