Introduction
In this How-To I will change my port from 80 to 79, probably because I want to host something else on port 80 not using IIS.
The way you setup this is in SharePoint it's to extend your Application, creating a new port 79. After making sure that it's working on 79 then you can change it to the default Zone, and delete the port 80 application. Here are the steps to change your port. Backup everything before making these changes.
Steps (3 total)
1
Adding the new port 79
In Central Administration -> Application Management -> Create or Extend Web Application -> extend an existing Web application.
Web application: select you actual web application normally ending with nameofyouserver-80. At this point you are extending you web application meaning SharePoint will be responding on port 79 and 80.
Select "Create a new IIS web site". On Description type "SharePoint – 79". On Port type 90. On Zone select any for now. Click OK. After couple seconds you should be able to see the new site on you IIS.
2
Removing SharePoint from port 80
Make sure everything its working fine on port 79.
In Central Administration -> Application Management -> Remove SharePoint From IIS Web Site.
After selecting your Web-Application on Delete options select you IIS Web site, normally "SharePoint – 80 (Default)". Delete IIS Web Sites select yes an click OK.
3
Make 79 the Default Zone
Central Administration > Operations > Alternate Access Mappings > Edit Public Zone URLs
Remove anything from the Default Zone and Move the 79 to the Default Zone.
Conclusion
BTW, Dont try to make this change touching IIS. Sharepoint setup IIS for you ( isn't that cool )
From: https://community.spiceworks.com/how_to/1159-changing-sharepoint-default-port-80-to-another-port-79
