I am sorry for my English. I have a problem.
Last year I bought 5pcs RB260GS(CSS106-5G-1Sr2) - all upgrades went fine.
Now I bought another 5, also CSS106-5G-1Sr2 - in all of them the upgrade failed. It was installed with older 2.11b firmware. I did the upgrade right out of the box, didn't set up anything else.
Upgrade does not work - I also tried manual upgrade, tutorials found on the forum. Is there any way to upload the firmware via tftp for example?

The interesting thing is that the old piece unpacked, which I had as a spare, went to upgrade me now. Also CSS106-5G-1Sr2.
Any ideas?

We are experiencing same issue; no upgrade and always default configuration at reboot. We have yet found 2 of this but we have a bunch of it new and never tested...

Is SWOS really so bad? I have 11 pcs RB260GS, firmware cannot be updated on 4 pcs. Why? Is it faulty HW, 4 pcs at once? Why can't I update the last 4 I bought and can I update the old ones?
They are all CSS106-5G-1Sr2 - do they really have identical HW?
I always upgraded immediately after purchase, with the default settings.
Is Mikrotik testing small RB260GS switches?

When I read the forum and the problems with SWOS, I don't understand that Mikrotik is selling this - it is damaging its reputation.

so again - is there a way to install the firmware using TFTP? If so, what firmware?
https://wiki.mikrotik.com/wiki/SwOS/RB2 ... S_firmware

Best to contact support, maybe they can provide a solution.
support@mikrotik.com

The procedure detailed on:
https://wiki.mikrotik.com/wiki/SwOS/RB2 ... S_firmware
is essentially a sort of what netinstall is for RoS (and it assumes that one has a Mikrotik router running ROS to act as TFTP server).
BUT:
1) it is specified that "RB260GS supports SwOS v1.7 till v1.17."
2) on the download page https://mikrotik.com/download there are TWO files related to RB260GS:
version 1.17 for RB260GS, RB260GSP:
https://download.mikrotik.com/swos/1.17 ... 0-1.17.lzb
and:
version 2.16 for new RB260GS(CSS106-5G-1S), new RB260GSP(CSS106-1G-4P-1S):
https://download.mikrotik.com/swos2/css ... 6-2.16.bin
3) the file to be used for TFTP in the example has the ".lzb" extension whilst the second SWOS file has the ".bin" extension
4) all posters are reporting their device to be CSS106-5G-1Sr2, a model that is NOT specified on the download page, likely "new RB260GS(CSS106-5G-1S)" is supposed to mean "CSS106-5G-1Sr2", but it is better to have a confirmation

Support should be able to disambiguate the contrasting info and provide a valid procedure.

I don’t think upgrade via TFTP is supported on newer CSS106. They tell to use manual upgrade with file load via WebUI.