Hi,
First, check to see whether the steps to embedded the Excel files are correct. Please refer to the following link:
http://office.microsoft.com/en-us/word-help/link-or-embed-an-excel-worksheet-HA010120810.aspx
Also, does this issue occurs in only one file or all the files?
Try to create a new file to check the issue.
If the issue still occurs, then try to start Word in safe mode to check the issue.
Jaynet Zhang
TechNet Community Support
