What is .REZ file extension?
Resource file used by OpenText FirstClass, a conferencing and emailing program that enables collaboration and communication between users; contains resources that customize the FirstClass interface; includes pictures, forms, icons, and sounds.
NOTE: REZ files are similar to .FC files except they only hold resources for the FirstClass interface instead of login data.
You can see a list of software programs here on easyfileopener.org that can open this file type so that you don’t need to search for it on the web. You can then open your file with this extension using a software listed below.