Misc Error Code 003-2101 After CFW

[hursit]

Hello people. I have some problems.
I have 2 different 3DS

1- Old 3DS XL
2- New 2DSXL

I was playing online games with my old 3ds with Sky3ds card. After that i made CFW for it. But now i cannot connect to the internet. There is an error code 003-2101.
Another New 2DSXL is connecting still. There is no error with it. I can play online games and can do everything. I test two of them with same wireless modem. I tried 3 different place with 3 different modem. But still same error with my old 3ds. But new 2DS is connecting. No problem.

I tried to change proxy , dns. And i tried to make it static ip. I try everything what is writing on the forums. But Still nothing.

What should i do do you think ?
Is it about the CFW ? If yes can i uninstall it. If i uninstall the CFW the version will be 11.5. Can i made it CFW again ? I have my nanddump from 11.3 version.

 

[ihaveahax]

looks like a internet connection issue. make sure internet settings are set up properly.

 

[hursit]

looks like a internet connection issue. make sure internet settings are set up properly.

ım sure it is setting properly. Bcs i can connect to the internet with other 2DS

 

[RY0M43CH1Z3N]

See this

All I had to do was unplug the modem, then unplug the router. After that plug in the modem first, wait for it to reboot and then plug in the router, wait for it to reboot and now it works.

 

[hursit]

See this

I tried this too. But still nothing

 

[hursit]

I fixed the problem.

I updated my Luma from 6.6 to 8.1. After update it didn't work still.
After that i downgrade the 3ds to 11.2 version. By the way i had my nand.bin backup. I kept that when i did CFW.

11.2 version connect to internet without problem. And i update again to 11.5.38 ( last FW ).
Now it is working properly. I can play online and everything

It wasn't about with the DNS proxy or another settings. It is about the CFW.

If someone will have same problem maybe he can try this way.