Hello feastabb,
The behavior you are seeing is not isolated to the ANSI C functions in CVI. The reason you are getting this error is because Excel attempts to lock all files it opens. Therefore, if you try to open the same file in another application with write access you will get an error. You can verify this behavior if you open the dat file in Excel, then open it again in Notepad. If you then make a change to the file in Notepad and try to save, you will get the following error:

There might be a setting in Excel Preferences to modify how the file is opened, but you could also try writing to the file in CVI, then opening it programmatically to avoid the file being opened at the same time in both applications.
Thanks
Message Edited by Wendy L on 09-28-2005 03:22 PM
Message Edited by Wendy L on 09-28-2005 03:22 PM
Wendy L
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