What is Google Pagerank Error?

I found some blogs with high PA and DA but when checking page rank, these site have error page rank. So what is PR error, please all guys explain to me? Thanks in advance.

Take a look at this bro, it might be useful for you:

http://www.blackhatworld.com/blackh...123-high-google-page-ranking-useless-now.html

I keep seeing the same question posted over and over, "Is Google PageRank Dead?" My thoughts are yes and no. Yes, it's dead to those outside of Google. No, it's not dead to Googlers (people who work at Google). In other words, I still think Google uses PageRank as a part of their organic ranking algorithm. I just don't think they will push PageRank out to the public anymore. A little research was made and came up with 10 signs, from which we can safely assume Google PageRank is dead to non-Googlers. While researching this topic, one thing I noticed killing off Google PageRank for non-Googlers has been in the works for a while. For years Google has been throwing us hints, and slowly removing PageRank data from our grasps, until one day it was gone.....