Getting "cfhttp.fileContent has length of -1"

Have a CF template that uses the cfhttp command to execute a template that extracts and formats data from the database.  When using the cffile command to write that information to a file:

<cffile action="WRITE" file="#pdffolder##getpdfid2.pdfid##client.account#letter.html" output="#cfhttp.filecontent#" mode="644">

the execution receives the message"

"cfhttp.fileContent has length of -1"

Trying to figure out how to determine the cause of this issue,

Regards

Weldon Moore