Populate textbox in new window

Hi guys,
Lots of threads and ideas, but I couldn't find what I'm looking for.
Hence, this.

I have asp page (say, 1.asp) that has a textbox. This page is available
to me in read-only mode, meaning I know all the field names, functions
names etc., but can't change anything.

Now, I need to write .htm or .asp (2.htm or 2.asp) that will have a
textbox and submit button. When user clicks on submit two things have
to happen:
1) 1.asp opens in new browser window
2) textbox in 1.asp gets populated with textbox value from 2.htm (or
2.asp)

It may sound like piece of cake, but it's turned into a problem for me.
Any help would be appreciated.

.

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