could the tension be too tight?

I have two Janomes and use Gutermann all the time, it's my favorite for the quilting machine.

I have used Gutermann 100% cotton in my Janome with no problems, I also use Connecting Threads- Essential thread in the machine too - no problems other than more lint which can be solved by using a q-tip and swipe it out before you load your next bobbin - also Coats and Clark. Sometimes a dealer might recommend one thread over another because it is something they personally had trouble with in the past or because they sell something else - my opinion.

I love Gutermasn cotton thread. It's my favorite for piecing.

Quilter4Hire's note is important information on whether to place the spool on the vertical or the horizontal spindle, based on which way the thread is wound on the spool.

Well after reading how many of you use Gutterman thread with no problems I guess maybe she (the LQS owner) had an ulterior motive after all for telling me not to use it.
Thank you everyone.
When my DGD go shopping for fabric and threads after Xmas I won't have to worry if she picks Gutterman.
Thanks

I found that Gutermann thread used to be really good because it had been made in Germany. For the last while it has been made in Mexico, and I find that the quality is not near as good. Just purchased a Pfaff quilt expressions 4.0 and my dealer recommended Aurifil. I am anxious to try the Connecting Threads thread. Seems like some of you think that is really good, and I know it is a lot cheaper. I have learned a lot the short time I have been on this site. Thanks again.

I also use pretty much any thread that I have. I inherited a bunch of thread with the stash that I got in February and I have found that Mettler is great for piecing, Connecting Threads for piecing, but I use Aurofil and Coats and Clark for quilting, sometimes Superior. the connecting Threads breaks and shreds for quilting. I love Gutterman hand quilting thread. It can't be beat!!!

Not my favorite thread either like many others though different ones for different uses trial and error

Gutermann is all I use on all my Janome machines and I have 5 of them. I find it does the best job. I am even going to try their serger thread.

I have a bernina and I was told not use coat and clark because of lint, I was sold to use gutermann. I have fould I have less lint. I was told not to use wal mart thread, it could rune your machine.