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Paste Special option is missing or not working in Microsoft Office
If your Paste Special option is missing, look here. Paste Special allows you to paste using the formatting of your choice.
You cannot open .xls files by using Microsoft Office Excel 2010
Describes a resolution to a problem in which you cannot open .xls files with Excel 2010.
This file is corrupt and cannot be opened, using Office 2010 email
Describes a problem in which you cannot open an Excel, Word or PowerPoint email attachment. You receive a “This file is corrupt and cannot be opened”, “Word Experienced an error trying to open the file" or "PowerPoint found a problem with content in...
Format 123456U to display as 12-34-556U?
I want to create a custom format that will display numbers such as 123456U as 12-34-56U, where numbers and letter at then end change from entry to entry.
Create a custom number format - Excel - Office.com
If Excel's number formats don't work for you, you can create a custom number format.