opencv_traincascade.exe error, "Please empty the data folder"?
I solved it!
I downloaded opencv and all other required programs on another computer and tried running train classifier on another set of pictures. After I verified that it worked in the other computer I copied all files back to my computer and used them.
I have been successful at training a classifier before but today I started getting errors. 
Problem:
When I try to train a classifier using opencv_traincascade.exe I get the following message: 
"Training parameters are loaded from the parameter file in data folder!
Please empty the data folder if you want to use your own set of parameters."
The trainer then stops midway in stage 0 with the following message:
===== TRAINING 0-stage =====
BEGIN
POS count : consumed   2 : 2
Train dataset for temp stage can not be filled. Branch training terminated.
Cascade classifier can't be trained. Check the used training parameters.
Here is how I got to the problem:
I had a parameters file inside the classifier folder where my trainer would usually train classifiers to. I forgot to delete this parameters file before running the traincascade.exe file. Even though I erased the parameter file I still got the same error. 
Thanks for helping.