Is it forbidden for me to shake hands with my close female friend when helping her fix her device, given that I have no sexual desire towards her?

Entering upon a non-mahram (definition) woman and being in seclusion with her is forbidden by the consensus of scholars, based on the Prophet's (peace be upon him) sayings: "Beware of entering upon women," and "No man shall be in seclusion with a woman unless a mahram is with her," and "None of you should be in seclusion with a woman, for indeed Satan is the third one." Therefore, it is obligatory to lower one's gaze and not speak to her except with ordinary conversation. She, in turn, must adhere to the legal hijab (definition) and not soften her speech, and always avoid seclusion, based on the Almighty's sayings: "Tell the believing men to lower their gaze," and "And tell the believing women to lower their gaze and guard their private parts and not expose their adornment except that which [necessarily] appears thereof," and "So do not soften your speech, lest he in whose heart is disease should covet."