CAEN Knowledge Base
CAEN Knowledge Base

Why can't I run certain software applications on CAEN Linux computers?

Some software applications in the CAEN Lab Software Environment (CLSE) for Linux have license terms that permit use only by individuals with a certain role at the University (e.g. a student enrolled in a course). If you have received an error message after attempting to run a software application on a CLSE Linux computer, it is likely either that your AFS token (the piece of data that proves your identity to the operating system) has expired, or that you do not have a required role at the University.

Refresh AFS Tokens

An AFS token is what CLSE Linux systems use to verify your identity and access to software. When you log in on a CLSE Linux computer, you are granted an AFS token automatically, but by default, the token expires after 25 hours. To refresh your token, type the following at a Linux command-line:

gettokens

You will be prompted to provide your UMICH password. Once you have refreshed your token, attempt to run the software again. If errors persist, see below.

The Software Application May be Role-Restricted

If you have refreshed your AFS tokens and still do not have access to run an application, it is likely that the software license is restricted by role. Depending on an application's licensing terms and one's role at the College of Engineering, individuals may not be able to run certain software applications in the CAEN Lab Software Environment. For example, regular staff or visiting scholars may not have access to the same software as currently enrolled students (see our online software listing for specific restrictions).

Individuals who would not otherwise be granted access to the Instructional or Research editions of software may request access to individual applications in the CLSE. Complete the CLSE Request for Software Access form to request access to a software application in the Student Instructional or Student Research edition. CAEN staff will review the license terms for the requested application, and grant access on a case-by-case basis according to eligibility and availability.