up a blind alley

up a blind alley

At an impasse; at a point where no more progress is possible or no solution can be found. I've gone around and around with various ways to fix this, but I'm just up a blind alley at this point. This merger is going to be up a blind alley if we can't resolve this legal dispute.
See also: alley, blind, up
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

*up a blind alley

Fig. at a dead end; on a route that leads nowhere. (*Typically:be ~; go ~.) I have been trying to find out something about my ancestors, but I'm up a blind alley. I can't find anything. The police are up a blind alley in their investigation of the crime.
See also: alley, blind, up
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

blind alley, (up) a

A dead end, either literally (a street or passage with only one entrance) or figuratively (a situation without hope of progress). The term dates from the sixteenth century.
See also: blind
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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References in periodicals archive ?
Even the most sophisticated new technology can occasionally send you up a blind alley - or a flooded tunnel.
And with tax cuts, tough talk on immigration and ranting about Europe, he's heading up a blind alley. Cameron's retreating to a traditional Tory platform with a green tinge.
The Government's own advisors have since admitted that the research led up a blind alley.
But that dichotomy runs up a blind alley, says Jenkins.