No Clintons allowed!

That’s what Hillary Clinton found out when she planned to rent office space in a tony midtown tower after she stepped down as Secretary of State.

Clinton had reached an agreement in 2014 to sublease the entire 32nd floor at 444 Madison Ave., and her staff was busy setting up a computer and phone network, according to emails — reviewed by The Post — from the Denver-based tech company that set up her private server.

The IT firm, Platte River Networks, was buying equipment, and arrangements were even being made for the upkeep of the office alarm system. The deal was so far along that Clinton’s staff was arranging for the care of plants left behind by a previous tenant, the emails show.

“Huma, Hello and welcome to 444 Madison!” reads an email to Huma Abedin, Clinton’s top deputy and the now-estranged wife of Anthony Weiner, from a representative of Rainier Investment Management.

The company, which had leased the space for two years, had entered into an eight-year sublease for the office with Clinton Executive Services Corp., the private company that runs the logistics for Clinton and her husband, former President Bill Clinton.

But as Abedin toured her boss’s future private office in early 2014 just days before the transition, the news came that the owner of the building — Westbrook Partners — was refusing to rent to Clinton.

“Huma was alarmed and flabbergasted,” said a source close to the negotiations. “She had a move-in date and had already arranged for the movers.”

The billionaire behind the Art Deco tower wanted nothing to do with Clinton, the source told The Post.

Westbrook Partners, a real estate investment firm, was founded by Paul Kazilionis in 1994. Kazilionis, 59, is a registered Republican who owns two waterfront mansions on Jupiter Island, Fla. and a $6-million home in Nantucket, Mass., public records show.

The company, which is close-lipped about its $20 billion global real estate empire, is known for its tough stance against tenants.

In 2009, property managers at 444 Madison tried to shortchange a 79-year-old Holocaust survivor who owned a deli in the lobby, according to a lawsuit filed by Andrew Spitz. Spitz claimed the property managers tried to block the sale of his business.

A spokesman for Westbrook wouldn’t comment on any political motives regarding the rental, saying only that the company didn’t want the hassle of a famous tenant.

“In light of the high profile nature of the proposed tenant, ownership determined that the burden and disruption to present tenants and building operations due to the level of additional security required was not in the building’s best interest,” said Frank Marino.

After Westbrook refused to rent to Clinton, Abedin scrambled to find space elsewhere in midtown. They settled on a building at West 45th Street, owned by Democratic donor Stephen Green.

Two workers outside that building on Friday said they didn’t even know Clinton had an office there.