iPad seems to be filtering emails - any ideas how to fix?

[engine]

Some e-mails, not spam, are invisible in the iPad. They are just not in any folder, yet, they are there. They show up on the iPhone, but not the iPad.
I checked by logging on to a webmail account, and they were there. Very odd, eh.

Any ideas?

[weeks]

Is this with the Gmail app or the Apple email?

[engine]

This is the Apple email client.
It would make some sense if it appeared in trash, if it was misdirected, but it's not there.
It's not an old message, it's a new one, so it should appear with the other recent messages.

[weeks]

I was going to suggest deleting the app and re-loading it, but you cannot do that yet with this Apple app. Try this:
Choose "take all accounts offline", and wait 10 seconds.
Choose "take all accounts online".

[engine]

Thanks.

Choose "take all accounts offline", and wait 10 seconds.
Choose "take all accounts online".

Where might i find that setting? I hunted around for it but couldn't find it.

[Sagacity]

I fixed mine using > mail settings > account > Days to sync > No limit. Be prepared for the mother payload of old emails to download.

[engine]

Thanks for the ideas.

So far, nothing has cured the issue, and the filtering continues.