Does your credential have local administrative privileges on that machine?
It might also be due to a firewall not being configured correctly.
These articles might also help:
Windows domain scanning requirements: https://www.lansweeper.com/kb/4/domain-scanning-requirements.html
Windows workgroup scanning requirements: https://www.lansweeper.com/kb/5/workgroup-scanning-requirements.html
How to scan a Windows computer: https://www.lansweeper.com/kb/164/how-to-scan-a-windows-computer.html
Access denied errors: https://www.lansweeper.com/kb/1/troubleshooting-guide.html
If they do not help I would suggest sending an e-mail to our support staff at support@lansweeper.com
