I can open one PDF file without problems, but, as soon as I open a second PDF, Acrobat DC freezes.
Happens with all PDF files!
Microsoft Windows [versão 10.0.17134.228]
Adobe Acrobat Pro DC version 2018.011.20058
As per the issue description mentioned above, Acrobat freezes when opening two pdf files, is that correct?
Could you try following troubleshooting steps:
1- Reboot the machine once if you haven't already and check if that helps.
2- If that doesn't work, try the steps given in this help document: Troubleshoot Windows system errors, freezes | Adobe software
Let us know if you need any help.