Dozens of students who reported sexual assaults to their university have said they were failed by complaints processes that left them traumatised.
A BBC investigation found universities received more than 700 allegations of sexual misconduct during the past academic year.
Students accused their universities of being paralysed by fear of reputational damage and not offering proper support.
Universities UK said institutions were making progress in handling complaints.
But students said they had to go through "traumatic" and lengthy complaints procedures, with one saying she "felt like the one on trial" and another calling it "a waste of time".
Freedom of Information responses obtained by File on 4 from 81 UK universities found more than 110 complaints of sexual assault and 80 allegations of rape were made last year.
In a number of cases students and universities also reported the alleged attacker to police.
However, there are no mandatory guidelines on how universities should investigate or record such complaints.
The result, campaigners and survivors say, is a "patchy" system that is failing students.
One student, who reported a violent rape to her university and police, was repeatedly forced to see her alleged attacker around campus because of a loophole in the university's safe-guarding procedure.
Women from multiple universities have also been dissuaded from coming forward on the grounds that the reporting process would be "traumatic".
One student said she was told by her university to spend the night in the library, after she told them she could not return to her accommodation out of fear of another attack.
Another described her experience as "like being 'gaslit' [a term for psychological abuse where victims are made to constantly doubt themselves and reality] on an institutional level".
'I felt like I was on trial' - Dani's story
Dani, 21, from the University of Cambridge, started having panic attacks after her supervisor sent her inappropriate and sexual messages.
On the verge of quitting her course, she tried to complain - but was passed around and given contradictory advice.
When she did manage to report it, she was warned eight times that she could face a harassment charge if she told anyone else about the allegations.
"Throughout the whole process I just felt like I was the one who was on trial," she told the BBC.
Before the disciplinary hearing, she asked to give evidence behind a screen - something commonplace in a court of law - but the university refused.
"I had to sit on the same side of the table just a couple of seats away from him, while I was cross-examined by his lawyer," she says.
Her complaint against him was upheld. But his punishment was to write a four sentence letter of apology and to follow a no-contact agreement that saw Dani - not her supervisor - barred from certain university buildings.
The man was allowed to remain at the university.
The University of Cambridge told the BBC it places the "utmost importance" on the welfare of its students and said improvements have, and will continue to be, made.
'It will ruin you' - Alice's story
Alice, not her real name, reported a student for "stealthing" - a term for when a condom is removed during sex without the other person knowing.
The person would "potentially be committing rape", lawyers say, because if you agree to having sex with a condom and remove it - without saying - then you no longer have consent.
After seeing a complaint on social media about the same student, Alice felt she had to come forward, despite hearing "so many horror stories" about her university's sexual misconduct reporting process.
Through social media, she spoke to eight women who had similar experiences with the same man.
A trail of emails, seen by the BBC, shows how she kept the university updated on what she found. But when Alice was waiting for a date for her preliminary hearing with the university, she was suddenly told her case was being dropped.
A rule change by the university's disciplinary committee meant her case no longer fitted its definition of "harassment".
Alice, who has now graduated, is "terrified" that the man remains on campus unchallenged - unless a current student decides to mount a fresh complaint under the new rules.
A University of Cambridge spokesman said: "We are doing everything we can to make sure students feel supported, and informed, regarding their choices". But the university said there is "always more we can do".
"It's a total waste of time," Alice says. "And it will ruin you."
What happens when a student complains?
Each institution is different, but normally the university appoints an investigator who takes witness statements.
Then a panel, made up of academic staff and sometimes a student representative, interviews the accused and the accuser before deciding whether the complaint should be upheld.
The process is supposed to be quick, but the BBC heard from one woman whose complaint of sexual assault took nine months to resolve - the entirety of her second year.
Some universities do not tell the accuser the outcome of their own complaint - viewing it as a matter between the institution and the accused.
BBC research found punishments for sexual misconduct ranged from expulsion to bans from university bars. Others were told to write letters of apology to victims.
At the University of Sussex, one sanction for sexual misconduct was a suspended £250 fine, only payable if the student got into trouble again before the end of that year.
Anna Bull from the 1752 group, which researches sexual misconduct in higher education, is calling for better regulation of complaints procedures.
"Universities have encouraged students to come forward and make complaints, but actually institutions are not necessarily safe to report to," she says.
Part of the problem, she says, is that universities police themselves - and while some manage this well, many do not.
Nicola Dandridge, chief executive of the Office for Students, England's independent regulator of higher education, told the BBC it would intervene in "serious examples of universities failing to address these issues seriously".
"But we will always be focused on making sure that our intervention is appropriate and in the best interest of students. It's not about punishing universities," she said.
Universities UK, which represents higher education institutions, urged universities to follow its voluntary guidelines.
Additional reporting by Larissa Kennelly