Simple input file convergence problem: scf optimize failed


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As the error message says, this error is most commonly associated with the calculation not reaching some convergence criteria in the allowed number of steps. Based on the output saying "scf optimize failed," my guess is that you ran out of steps in the geometry optimization. Given that you are optimizing water and have given the geometry optimizer 1000 steps to find the minimum, there is probably something wrong with your build (also I can run the exact input you posted without issue). So you are going to have to look earlier in the output to see where the calculation went wrong.

Do you get reasonable energies from the SCF calculation?
What is happening to your geometry during the optimization?

Below is the optimized geometry that I get when running your input file as posted.
O       0.00000000     0.00000000     0.15623523
H -1.48376846 0.00000000 -0.85312448
H 1.48376846 0.00000000 -0.85312448
And the SCF energy at this geometry was
Total SCF energy = -75.985359176239
Check to see if your build produces the same energy and whether it also shows that the energy gradients are essentially zero (task scf gradient).