Hi,

Can you explain you want to add link on catalog item to an attachment?

you can use UI macro variable to show the link of attachment; if you want users to click that link and download the file then the link should include sys_attachment table in the url

sys_attachment_doc stores the metadata about attachment

sample UI macro script below

Give the sys_attachment record sys_id in the url in place of sysID

<?xml version="1.0" encoding="utf-8" ?>
<j:jelly trim="false" xmlns:j="jelly:core" xmlns:g="glide" xmlns:j2="null" xmlns:g2="null">

	<div>
		<p>
			<span style="font-size:20px">If you need access, please click
				<a href="/sys_attachment.do?sys_id=sysID" rel="nofollow">Click here</a>
			</span>
		</p>

	</div>

</j:jelly>

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Thanks
Ankur