If you paid for the Category-6 cable, you wasted the difference in price between it and the Category-5E cable. I seriously doubt you have the skill, experience, proper tools, and tester to install the cable and test it to pass the Category-6 test suite. Experienced installers have trouble with Category-6 installations. Did you follow the standards regarding maximum pull tension and minimum bend radius? Exceeding either of those will damage the cable, and solid-core cable is fairly fragile, and STP even more so. A break in the shield will render it useless since it must be continuous from end-to-end.
The wire is a drain wire to aid in grounding. The shielding must be connected to a proper ground. You must use equipment which can properly connect STP for grounding, otherwise you wasted money on shielding. Most business-grade equipment can do this since the equipment requires grounding, but most consumer-grade-equipment does not properly ground STP.
You should also be familiar with ANSI/TIA/EIA-570-B Residential Telecommunications Infrastructure Standard. For instance:
6.2 100-Ohm UTP cabling
6.2.1 Bend radius
In spaces with UTP terminations, cable bend radii shall not be less
than four times the cable diameter for outlet cable.
6.2.2 Pulling tension
The maximum pulling tension for a 4-pair 24-AWG UTP cable should not
exceed 110 N (25 lbf).
6.2.3 Connecting hardware
Cables should be terminated with connecting hardware of the same
category or higher. Installed transmission performance of components
that meet requirements of different performance categories shall be
classified by the least performing component in the link (e.g.,
cables, connectors, and patch cords that are not rated for the same
transmission capability). This performance category should be marked
on the connecting hardware or noted in the administration records.
Only remove as much cable jacket as required to terminate connecting
hardware in order to maintain cable the geometry. When terminating
connecting hardware, preserve pair-twist as close as possible
SP-3-3490-RV2 (To become ANSI/TIA/EIA-570-B) to the point of
mechanical termination 1 n. For category 5e and category 6 cables, the
amount of pair untwisting as a result of termination to connecting
hardware shall be no greater than 13 mm (0.5 in). For category 3
cables, the untwisting shall be no greater than 75 mm (3 in). . A
minimum of 200 mm (8 in) of excess cable should be stored at each
6.2.4 Cross-connect jumpers and patch cords
Cross-connect jumpers and cables used for patch cords should be of the
same category or higher as the outlet cables to which they connect.
Due to the variety of cable types, connecting hardware types, tooling
and testing required, field termination of patch cords is not