@Zoltán , From your description, I know the Configuration client install failed on company network. Could you let us know if it affects all the devices on the company network or just a few devices?
For the error message, based on my research, it can occur if there is an invalid or corrupt copy of C:\Windows\System32\msvcr120.dll on the target system.
We can manually install the configuration manager client on the affected client to see if it is working, If the result is the same, we can rename the existing copy of msvcr120.dll and then copy over msvcr120.dll from a working client. Once the file has been copied over, reboot the problem client and attempt the installation again.
Hope it can help.
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