user2881: Nightky Sin just posted a duplicate of his original question. 
I think I remember him asking the same question 2 hours after his first question. That question was most likely closed.
So my question is; how can I verify that this is indeed his third attempt at asking the same question all over again?
(And thus be a bit more harsh in pointing this out in the comments)

user10794: You can find the user's ID (click on his/her profile) - yours is 2881. Then do a search in the ordinary search box. You will probably find that the user number is already filled in, in the search box:

You can then add deleted:1/deleted:yes to search for deleted posts (if you have enough reputation):
user:2881 deleted:1

Or, you can search for closed questions with closed:1/closed:yes:
user:2881 closed:1

You can filter this even more by adding the is:question option:
user:2881 closed:1 is:question


A user that keeps asking low-quality questions will probably eventually encounter a question-asking block, as part of Stack Exchange's system for keeping questions of good quality. See What can I do when getting “We are no longer accepting questions/answers from this account”?

2881: <p>Nightky Sin just <a href="https://arduino.stackexchange.com/questions/30200/adc-interrupt-from-nick-gammon">posted a duplicate</a> of his <a href="https://arduino.stackexchange.com/questions/30106/ac-meter-by-adc-timer-interrupt-from-nick-gammon">original question</a>. </p>

<p>I think I remember him asking the same question 2 hours after his first question. That question was most likely closed.</p>

<p>So my question is; how can I verify that this is indeed his third attempt at asking the same question all over again?</p>

<p>(And thus be a bit more harsh in pointing this out in the comments)</p>
 10794: <p>You can find the user's ID (click on his/her profile) - yours is 2881. Then do a search in the ordinary search box. You will probably find that the user number is already filled in, in the search box:</p>

<p><a href="https://i.stack.imgur.com/FySDt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FySDt.png" alt="Search for posts by a user"></a></p>

<p>You can then add <code>deleted:1</code>/<code>deleted:yes</code> to search for deleted posts (<strong><a href="https://arduino.stackexchange.com/help/privileges/moderator-tools">if you have enough reputation</a></strong>):</p>

<pre><code>user:2881 deleted:1
</code></pre>

<p>Or, you can search for closed questions with <code>closed:1</code>/<code>closed:yes</code>:</p>

<pre><code>user:2881 closed:1
</code></pre>

<p>You can filter this even more by adding the <code>is:question</code> option:</p>

<pre><code>user:2881 closed:1 is:question
</code></pre>

<hr>

<p>A user that keeps asking low-quality questions will probably eventually encounter a question-asking block, as part of Stack Exchange's system for keeping questions of good quality. See <a href="https://meta.stackexchange.com/questions/86997/what-can-i-do-when-getting-we-are-no-longer-accepting-questions-answers-from-th">What can I do when getting “We are no longer accepting questions/answers from this account”?</a></p>
