WD RED with C5 Current Pending Sector Count

hi,

my drive is a wdc wd60efrx (red 6TB).
i have it less than 3 years, more than 2.

I notice there is a file i can’t copy and it freeze each time the system (win7 x64). This file was in the very very very end of the last partition, last space (almost full disk is used, less than 500Mb).

When i perform a test with Crystal Disk Info 8.5.2, it said CAUTION and there is the c5 line : Current Pending Sector Count with 200 value.

what should i do ?
perform a check disk ? under dos or under windows ?

should i contact the reseller or the WD rma ?

is there a trust way to know what files are impact from this 200 “sectors” ?

for me, the RED one should be the most quality, so why is this happening ?