Hello, I am doing upgrade from OJS 2.4.8-1 to OJS 3.0 of one journal with more than 600 articles. I experienced difficulties that some articles are in upgrade to 3.0 disoplayed twice (one without articles and one with proper articles). Some issues of journal are missing and in some it is written that there are 14 articles but pdf files are not there.
During upgrade I got information that upgrade was successfull.
Please see attach which presents duplicate entries.