Hi Adnan,
Your results are likely not going to be correct. This phrase means that one component was unable to successfully converge on a stable solution (usually a fiber or optical amplifier where differential equations are required).
I recommend locating the component that has this warning and trying to change the settings. This is not always easy to fix but it usually results from a large number of input channels, very high powers, not enough sections/iterations for the numerical algorithm, etc). Cheers.
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