As shown in the figure below, in the windows 10 system, all the services related to DB2 have been started, and db2start has been executed. My host name is localhost, port: 50000 (the port exists in the etc / services file). I use the default account at the time of installation: db2admin. I also tried with the current account admin and password, and failed. Based on the above conditions, please take a look at what is wrong.