Small Engines (Lawn Mowers, etc.): Poulan-Pro PPB250E Trimmer, starter rope, spark tester

Question
John, I have a Poulan-Pro Link Trimmer that won't start.  The starter rope is ok, it appears to get gas as the primer balls fills when pressed. No sure if it gets fire though?  What should I do?

Answer
  In general, I remove the air filter cover and filter, and squirt some carb cleaner in the carb and try to start, if it starts and
dies, then you know that the problem is likely in the carb.
   Definitely, dump out the old fuel, and try some fresh, as gas goes bad quickly these days.
  If you can't get a hit from the squirt, then try a new plug,
as it could just be fouled.  One can test for spark with a plug,
but a shielded spark tester is much safer, as the spark can ignite
gas fumes.
   Try these things and let me know what you find.