change default open size in Acrobat Pro XI

Open up Acrobat's preferences, go to the "Page Display" category and change the default zoom level from "Automatic" to e.g. 100%. This will only work for documents that do not have their own default zoom setting.

Hi

you can paste this script it will helpful for your and other also while open the document in same size

On Left hand side you can find "Page Thumbnails"

Select the First Page and Right Click then

Select the Page Properties then dialog box while open Select the "Action Tab"

There you can find "Select Action" DropDown in that Select "Run the Javascript"

Javascript Editors while open there you can Paste

this.zoomType = zoomtype.fitP;