These odd symbols are the hidden field codes EndNote uses to hold reference information in your document. To solve the problem try the following steps:

1. In Microsoft Word, click on the EndNote tab and make sure that 'Instant Formatting' is turned on (in the Bibliography command section of the ribbon toolbar).
2. Go to File > Options > Advanced, then under the 'Show Document Content' heading make sure that the 'Show field codes instead of their values' box is unticked.
3. In the Bibliography command section of the ribbon toolbar, under 'Convert Citations and Bibliography' click the option 'Convert Word Citations to EndNote' then click the 'Update Citations and Bibliography' option above.