[solved] Gpg-agent cannot find key card

Hello,
I used my Nitrokey key card successfully with Win10 until I updated and rebooted the system.
Since then I get this output for command gpg --card-status:

C:\Users\d038783> gpg -vvv --card-status
gpg: using character set 'CP850'
gpg: selecting card failed: No such device
gpg: OpenPGP Karte ist nicht vorhanden: No such device

The logfile of scdaemon are pointing to failing service:

2021-05-26 11:13:06 scdaemon[3956] DBG: chan_0x000002a0 -> D 2.2.27
2021-05-26 11:13:06 scdaemon[3956] DBG: chan_0x000002a0 -> OK
2021-05-26 11:13:06 scdaemon[3956] DBG: chan_0x000002a0 <- SERIALNO
2021-05-26 11:13:06 scdaemon[3956] DBG: enter: apdu_open_reader: portstr=Yubico Yubi
2021-05-26 11:13:06 scdaemon[3956] pcsc_establish_context failed: no service (0x8010001d)
2021-05-26 11:13:06 scdaemon[3956] DBG: leave: apdu_open_reader => slot=-1 [pc/sc]
2021-05-26 11:13:06 scdaemon[3956] DBG: chan_0x000002a0 -> ERR 100696144 No such device <SCD>
2021-05-26 11:13:06 scdaemon[3956] DBG: chan_0x000002a0 <- RESTART
2021-05-26 11:13:06 scdaemon[3956] DBG: chan_0x000002a0 -> OK

In Win10 Device Manager there’s a smart card reader
“Microsoft Usbccid Smartcard reader (WUDF)”

Is there a conflict with Nitrokey and service rscd?

Please advise how to fix this issue.

THX

Root cause identified:
Service “SCardSvr” was not running.