San Francisco building officials issued yet another violation Tuesday against the Millennium Tower after city-ordered inspection crews found another cracked window at the troubled high-rise.

The latest cracked window was found during an inspection last Wednesday. That exterior inspection came after NBC Bay Area first reported about a window that cracked unexpectedly on the 36th floor over Labor Day.

The failure, Millennium officials and their consultants have repeatedly asserted, amounted to an isolated incident in unit 36B on the Mission Street side of the structure, where scaffolding is still in place.

They blamed an exterior impact of an unknown origin, not the tilting and sinking of the structure.

The city announced it was satisfied with that explanation after its own engineering consultant backed it up.

But then came the latest discovery, which involved a crack between the 9th and 10th floors on the Fremont Street side of the building. City officials say consultants hired by the owners, Allana, Buick and Bers, do not know what might have caused the newly discovered failure.

Meanwhile, Millennium officials told the city they hope to remove the cracked glass as soon as Wednesday, but the city issued a new violation notice against the owner, seeking more study and the reinstallation of the protective scaffold on Fremont Street by Friday.

William Strawn, spokesman for the Department of Building Inspection, said the city has been told building owners will take out the window and it will not impact the weatherization of the building.

“They will likely request that DBI withdraw the issued (violation notice) and the requirement to restore the protective scaffolding,” Strawn said.