how long should I wait for the notice ?

[h1blues]

When USCIS sends a notice in the mail asking for more evidence, how long should we wait for it before contacting them if it never arrives? it has been more than a week since I saw it on the website, but no mail so far ?
I dont want the case to get abandoned.

[canadianinmd]

Hey, I would give them two weeks tops. Then call them if it has not arrived.
I have heard of many people who have waited 2 weeks for that information.