Sometimes my "mailto:" function works inside a browser (more specifically Google Sheets), sometimes it doesn't

So, sometimes my "mailto:" function works inside a browser (more specifically Google Sheets), sometimes it doesn't.

I have on a Google Sheet a spreadsheet, where when I click on the cell, it pulls up the following if statement which contains a mailto: instruction so that a form email is created in a mail client, like Outlook.

Here it is:

=IF(Q2>0,HYPERLINK("mailto:"&Q2&"?CC=sales@clickitco.com&Subject="&Letter!A$2&"&body="&Letter!$B$2&" "&$AE2&",%0A%0A"&Letter!$C$2&"%0A%0A"&Letter!$D$2&" "&$B2&"%0A%0A"&Letter!$E$2&"%0A%0A "&Letter!$F$2&"%0A%0A "&Letter!$G$2&"%0A%0A "&Letter!$H$2&"%0A%0A "&Letter!$I$2&"%0A%0A "&Letter!$J$2& "%0A%0ASincerely,","email"),"")

The cells it refers to are paragraphs of the email.

Sometimes this works, sometimes it doesn't. I have look at the browser's pop-up blockers, the restrictions on any java, etc. Nothing seems to prevent this from creating an email. I have tried it in Chrome and Explorer, the current versions of each. I have tired it on several versions of Windows, fro 7 to 10. Same results.

I am posting it here hoping to find someone who has an answer.

Thanks to anyone who try and figures out this problem.