When someone thanks you for a job, action, help that has not even been started. Now you are obliged to carry out the action for them.
The teacher pre-thanks the technician during their text conversation:

Teacher: My Computer is going crazy. It is shutting down and flickering sporadically.

Technician: OK, I will be there later today to take a look.

Teacher: Oh, Thank you so much!
by CAR1999 December 20, 2012
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