How to generate GUID & UUID in LR Script

his the first time I am working capturing GUID. I gone through your forum and tried, was able to generate GUID and when passing the value the appllication throughing 400 error. Can you please help me out. In my script there are lot of UUID, do I need to worry about them.

Actual Request:

web_url("AuditDB.jsp",
"URL=">XXXXX/.../AuditDB.jsp
"Resource=0",
"RecContentType=text/html",
"Referer=",
"Snapshot=t35.inf",
"Mode=HTML",
LAST);

Passing value;

lr_guid_gen();
lr_message("%s", lr_eval_string("lrGUID"));

web_url("AuditDB.jsp",
"URL=">XXXXX/.../AuditDB.jsp
"Resource=0",
"RecContentType=text/html",
"Referer=",
"Snapshot=t35.inf",
"Mode=HTML",
LAST);

 

Error:

Action.c(720): Error -26631: HTTP Status-Code=400 (Bad Request) for