Thank you for your question.
I am sorry you are having a problem with the trimmer. I see that Joseph P. has given you a few good links for repairing the starter on a trimmer. If the spring has come out of the spring plate, it can be tricky to get it back in. First, hook the outside end into the plate. Then work the rest of the spring into the plate. You have to keep turning the plate while pushing the spring in. The image below shows how the spring should look when it is installed correctly. If you do not have any luck installing the spring into the plate I recommend ordering a new spring. It will come already installed. Once you have the spring installed reassemble the starter, using the videos Joseph P. has give as reference.
I hope this is helpful. Please let me know if you need further assistance.
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services
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