BM4T-LB & Danfoss - modbus communication issue

Hi @maurice and @chelsea!
I’m not succeed with writing holding registers for a few Danfos devices.

AK CC 550A (ID:111)
I can read and WRITE register:
REG1012: Defrost start ->1
I can read register and can’t write1:
REG116: Main Switch ON → 1 / OFF → 0

10 REM 11.111.MB_REG1012 = VAR10
20 WAIT 00:00:02
30 VAR11 = 11.111.MB_REG1012
40 REM 11.111.MB_REG116 = VAR15
50 WAIT 00:00:02
60 VAR16 = 11.111.MB_REG116

VLT FC51 (ID:1)
I can read registers. But I can’t write them.
REG49999: Run ->1148/ Stop → 1048
REG50009: Frequency 100% → 16384 / 0% → 0

10 REM 11.1.MB_REG50009 = VAR1
20 WAIT 00:00:02
30 VAR2 = 11.1.MB_REG50009
40 REM 11.1.MB_REG49999 = VAR5
50 WAIT 00:00:02
60 VAR6 = 11.1.MB_REG49999

So only one thing that I can do it is send Danfoss AK-CC 550A to defrost.
//If I use another controller instead LB I can change all of those registers without any problems, but still prefer to use LB.

Do you have any ideas? any suggestion?
Thanx by the way!

Thanks for your test, there was a problem when writing to third-party devices. we have already fixed it in latest firmware rev64.3. you can update by T3000.exe automatically.
T3000->Help->Check for update

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Thanks for you answer @chelsea,

I’m trying to update T3-LB to 64.3:

Your computer has multiple network cards, and it may not be clear which one is when updating with ISPtool, you can try to disable unrelated network cards, or you can directly use T3000 to automatically update

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Ok! I will try.