There's no immediate end in sight to trouble that has hit the U.S. State Department's computer system for processing visa applications and caused problems for thousands of people worldwide.
"We're still working on it," said State Department spokeswoman Marie Harf, who declined to give an estimate for when it might return to full service.
The problems began last week when a software patch was applied to the Consular Consolidated Database, an Oracle database system that contains hundreds of millions of visa applications and photographs.
"Our system was experiencing intermittent performance issues for several months leading up to July 20, when we patched it trying to address the issue," said Harf on Wednesday at a televised news conference.
"The Bureau of Consular Affairs updated the software, as had been recommended by the company, however our database began experiencing performance issues shortly after maintenance was performed," she said.
Harf repeated the department's previous assertion that it sees no malicious intent in the incident.
"We believe the root cause of the problem was a combination of software optimization and hardware compatibility," she said.
The problems have created a backlog in applications, which are being dealt with in the order in which they were received, said Harf. The backlog should diminish as additional servers are brought online, but she had no precise schedule for that.
The State Department made special arrangements for delegates heading to next week's U.S.-African Leaders Summit in Washington, D.C., but others haven't been as lucky. The State Department's Consular Affairs Facebook page has many complaints from people who haven't been able to get visas and hold non-refundable flight tickets.
The Consular Consolidated Database is accessed by staff at U.S. embassies, consulates and domestic offices worldwide and ties together information from numerous databases on travelers coming to the U.S., those in the country and those that have completed trips in the past.
Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn's e-mail address is email@example.com