How to delete all 3000 mail in my inbox on my iPhone 4ios?

How can I delete all 3000 mail in my inbox on my iPhone 4ios?

There are options on how to delete emails
First, when in the Full Featured version ALL
of your emails are on one page. You have to
scroll down to see them all.

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Place a check mark in the empty box at the top
left above the inbox which then places a check
mark in All of the boxes to the left of your emails.
If you want to save some you will have to scroll
down thru your emails and remove the check
mark to the left of the one you want to save… You
can remove the check mark by clicking on it…
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Clicking on the down arrow to the right of the above
box brings up options to delete.
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On occasion placing the check mark as described
above does not place a check mark in all of the
empty boxes. In that case just repeat the
procedure until they are all gone. The below
method usually does.
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You can also click the box next to the first message
you wand to delete and then hold down the Shift key
and click the box next to the last message you want
to delete. All messages in between will be highlighted
and can be deleted at once. If you want to save any
of the emails scroll down and remove the check mark
mark by clicking on the check mark to remove it.
Some users will scroll to the bottom… Place the
check mark to the left of the last email then click on
the UP arrow on the right side that takes you back
to the top and then hold down the Shift key and
place the check mark on the first email.
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For just a few emails you have the option of clicking
on the TRASH can that will display when you hover
your pointer in the open space between the
SENDERS name and the SUBJECT matter or
placing a check mark in the box to the left of the
Senders name and then clicking on DELETE.
On occasion a glitch will occur and they will
not delete… Click on the F5 key to refresh the
page and repeat the above procedure.
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BASIC FORMAT
Hover your pointer over the GEAR… Upper right.
.click on SETTINGS… Click on VIEWING EMAIL.
Place a check mark left of BASIC… Click SAVE.
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To move from one page forward/backward click
on the single arrow on either side of the page
number… Upper right. Clicking on the double arrow
will send you back to the start or end depending
on which double arrow you click on
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Click on SELECT ALL… Top left… Then click on
DELETE… For a few the TRASH can is located
on the far right or place a check mark in the box
to the left… Click on DELETE
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These links explain the new method
EMAILS & TRASH

EMAILS

ANDROID MOBILE