Garmin Fenix 5X plus charging connection will not work!

Try another cable. Some users indeed have problems with cables, even quite new out of the box, though the majority of owners have no problems. Perhaps there was a bad batch of cables. If you do not get a replacement from Garmin, get one from eBay - they are innexpensive.

... also, preferably charge the watch using an USB port of a computer, than a socket charger.

No, better not use a USB port of a computer. If you loose connection due to bad connector design (which happens quite often) and your watch was not properly ejecten your watch might freeze or even crash (It even crashed so bad, it wouldn’t start and I had to factory reset it)

I only connect my watch to my computer for updates.

nick1098s said:

I’ve probably bought over 20 cables over time

Hm, strange. I still have the orginal cable (1½ years old watch), and have no problems with connection whatsever. I have an Instinct though. I see complaints about charging on the Instinct forum only exceptionally, and when, then it is a cable problem. Can't speak for Fenix 5 personally, but a friend who has it since 2 or 3 years has no problems with charging either.

Do you rinse the watch after activities, where you sweat a lot, and after swimming (especially after salt-water dips)?

Elbo said:

your watch was not properly ejecten your watch might freeze or even crash

The storage can get corrupted only when it is simulatenously being written to, in the moment of the disconnection. Nothing will happen if you have no Garmin Express active on the computer, since nothing else will write to the device.

USB port is recommended for the charging because of better tension stabiity, and less AC noise than at many chargers (especially the low-cost and miniaturized ones). While at medium and bigger size devices (such as phones) it plays no role, at a watch that has no space for bigger capacitors for stabilizig and filtering the charging tension, it may pose problems, and often it indeed does.

nick1098s said:

Are you going to have better connections in the future Garmin?

This is basically a user forum for mutual help. Garmin rarely answers any questions here. You better call the Customer Support for any questions.

For charging use a high capacity charger, not a cheap one and not the computer! If you have connection issues it sometimes helps to compress the connector a bit in the middel with tongs.

Elbo said:

No, better not use a USB port of a computer.

I've only ever used a USB port on the various computers I've had, to connect and charge the different watches I've had and still have.

As someone else has said, I still have some older cables from earlier watches that have been used extensively and they do still work fine. I also have had cables stop working and replaced them with new ones possible because the tolerance of the socket and the cable plug are at opposite ends resulting in a loose fit.

It is important always to ensure that the socket on the watch is clean and dry before plugging a cable in.

trux said:

Try another cable. Some users indeed have problems with cables, even quite new out of the box, though the majority of owners have no problems.

^^^^^^THIS^^^^^^^^^

With the watch not connected, hold three buttons down (light, down and start buttons) for 15-20 seconds and try charging again.