If you are unable to register for a particular class, take note of the error message displayed on the screen before contacting the Office of the Registrar about the registration error. It makes it easier to troubleshoot the registration error. Common errors/restrictions are listed below, along with corresponding instructions to resolve the specific error that is preventing you from registering from the class.

Error Message

What It Means

What You Should Do

Prerequisite or Test Score

A required prerequisite course(s) or test score has not been completed satisfactorily. To determine if you are eligible to access the course, contact the department hosting the course.

Student is missing the prerequisite requirement or test score for a course. Course requires a minimum grade in another course or minimum test score as a prerequisite condition.

Turn in the required test score before attempting to register or receive a minimum grade for the required prerequisite course before registering for the subsequent course.

Link Course Required

This course is linked with a lab, recitation, or studio. You must register for all parts of the course. Check the Schedule of Classes to find the linked CRN, and register for both at the same time.


Section is linked to another section of a course – e.g. lecture linked to lab/recitation or studio. These sections must be registered for at same time.

Add all required sections at the same time by entering all required CRNs into the CRN boxes of the add/drop page in Online Services at once and press the “submit” button to register.

Field of Study

Restricted by major, minor, or option.

Students that do not meet the requirement(s) are ineligible to register for this course. Questions should be referred to the department hosting the course.

Course is restricted to students in a specific major/minor that match the field of study associated with the section and the student is not listed in the required major/minor for enrollment in the course.

Select another section that is not restricted outside your major/minor or contact the department for an override.

SAPR-Department Approval


Approval is needed from the department to register for the course

Email the department responsible for the course. If department approves, then student will be granted an override permission to be allowed to add the course.

Maximum hours exceeded

Student may not exceed the maximum credit hours allowed for their level. Attempting to register for more credit hours than you are approved to take for the term.

Reduce course load or request to increase credit limit for the term, submit an extra credits petition

Open – Reserved for Wait List

Attempting to register for a course that is full. Departments mark a class/section “open” or “closed” when registration is full – waitlist is available.

Waitlist for the course

Level Restriction

Course is reserved for a different student level, i.e. an undergraduate student attempts to register for a graduate level course.

Select another course that is allowed for your level.

Closed Section

Course has reached enrollment capacity set by the department.

Select another section that is open and has not reached enrollment capacity.

Campus Restriction


Course is restricted to students on a specific campus – i.e. Corvallis campus student attempting to register for a course offered at Cascades campus or through Ecampus.

Look for classes offered at your “home” campus.

Class Restriction

Course is restricted to specific class standing (freshman, sophomore, junior, or senior) and the student’s classification does not match the required classification for the course.

Wait until they reach this class standing requirement.

College Restriction

Course is restricted to students in a specific college, and the student is not listed in the required college for enrollment in the course.

Search for a course section that does not restrict registration by college.


Requires registration in an associated co-requisite course. Enter the CRN for each co-requisite in the Add Classes Worksheet of your online registration.  Submit the changes simultaneously.

Course requires registration in a co-requisite course at the same time.

Add both classes at the same time by entering in both CRNs during registration.

Open – Waitlist Filled

Course has reached enrollment capacity, including waitlist seats set by the department.

Search for another course section that has available seats in class or with available spots on the waitlist.

Time Conflict

Time of course conflicts with another course on the student’s class schedule.

Find another section that does not have a time conflict (overlapping or double-booked) with the course(s) you are already registered for, or decide on other courses that do not conflict with your schedule.

Duplicate Course

Course is a duplicate of another course already on the student’s schedule – attempting to register for the same course twice.

Check to make sure you have entered the correct CRN during registration.

Registration changes are not allowed. Course status dates not within range of part of term.

Attempting to add/drop course that has a restricted add/drop deadline.

Find another section within the add/drop deadline or submit a Petition for Late Change of Registration to request a late add/drop.