Unisa has extended its registration period at all its campuses until a strike by workers affiliated to the National Education, Health and Allied Workers' Union (Nehawu) is resolved.
Registrations were due to close on Friday.
Students were prevented from entering at least four campuses on Thursday morning due to the protests over wages.
Nehawu says its members are demanding a 14% salary hike across the board, while management is offering only 4.5%.
Wage negotiations reached a deadlock on Wednesday following months of talks.
The university's Mandla Makhanya says the institution doesn't want students to be penalised because of the strike.
“We are very concerned about our students being affected. The majority of our students are registering online, but some of our students require assistance on campus.”
But Nehawu's Khaya Xaba says the university is wasting money on other things instead of paying staff better salaries.
“That’s one of the reasons they can’t pay the workers money, because they’re busy spending their money on useless things.”