The users with a lack of technical knowledge do not know how to change it. Port number of server: Changing the Port Number of the server also helps in solving such problems. This method will surely make to come out from such error issues. As soon as you look at such an issue, uninstall your MS outlook software and reinstall it again. Reinstallation: When your software is outdated or it is installed with a corrupt or pirated website then such an error type of issue occurs. Error while setting up the MS outlook software. However, there are three main reasons which had been described by the technical experts. There are many reasons which are responsible for these insecure connections. It pop-up on the outlook Dashboard with some numbers written as Failed to attach to the server.Socket Error 10051 Error Number. Microsoft Outlook PII error is a type of issue which disturbs the MS Outlook applications while someone is working on it. Along with these PII also has a record which includes the information which is linked to an individual such as educational, employment, medical, finance, etc. PII stands for personally identifiable information and this is a type of information that is maintained by the agency that uses it to trace the individual identity which includes, date of birth, birthplace, Social security number, name, biometric records, mother’s maiden name, etc. What Exactly is PII (Personally Identifiable Information)?