To solve this problem, you need to obtain a copy of the missing file csapi3t1.dll and place it in the folder "Program Files\Common Files\Microsoft Shared\Proof". After have done this, you may need to restart Windows. You should also verify that "Always check spelling" is enabled in Tools, Options, Spelling.
The missing csapi3t1.dll file is included with Windows XP, it simply isn't installed by default. You can install it from the i386 folder on your Windows XP CD. (If you don't have a Windows XP CD, your computer manufacturer should have created an i386 folder somewhere on your hard disk.)
To use the version provided with Windows XP, click on Start, Run, then type:
expand d:\i386\csapi3t1.dl_ c:\csapi3t1.dll
and click OK (if necessary, replace "d:\i386" with the true path of your i386 folder.) A command window should flash up on your screen and then vanish. Now look for the file in the C:\ root folder using Windows Explorer, and move it to Program Files\Common Files\Microsoft Shared\Proof using drag and drop. If you use this method, be sure to get the filename correct (the end of the filename is number three, letter T, number one.)
If you can't find an i386 folder, you might find a copy of csapi3t1.dll somewhere on your Microsoft Office CD. Copies may also be extracted from the file mailnews.cab in an Internet Explorer 5.0 or 5.5 distribution set, the file win98_27.cab on a Windows 98 CD, or the file Win_10.cab on a Windows Me CD. Alternatively, you can download a copy of the file by clicking on this link -
http://www.tech-pro.net/files/csapi3t1.exe -. Just run the downloaded file to install it into its usual location.
If this doesn't help, try copying csapi3t1.dll to the Outlook Express folder instead. Some readers have reported that this works when all else has failed.
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