Thousands of A-level students have been left on tenterhooks as the official website which tells them whether their grades have earned them a university place had to be taken down because it was inundated with inquiries.
UCAS said it had been forced to shut down its Track website temporarily after traffic to the site quadrupled.
UCAS said in a statement: "Traffic to the Ucas Track website is four times the peak per second compared to last year.
"In order to secure a full service, we have taken the site down for a short time.
"Full service will be resumed shortly and we apologise for any inconvenience.
"All other Ucas websites, including the clearing vacancy service search function, are still available.
"Importantly for applicants, the ability to choose a clearing place will not be impacted and this function will open late afternoon as planned."
* UCAS advisors will be taking part in a live Q&A on the Birmingham Post website today (Thursday) between 12-1pm and 6-7pm at www.birminghampost.net/ucas