The Bleeping Computer AdwCleaner download page
includes the following note.
Under rare circumstances, you may lose your Internet connection when running AdwCleaner. This is typically due to an adware being removed that was acting as a proxy. To resolve this you can use a tool like RKill, which will automatically reset your Internet settings so that they are not using a proxy...
Internet connectivity problems can occur for a variety of reasons
to include corrupted networking software installation, third-party software inserting itself into the network adapter settings, misconfiguration or corruption issues with TCP/IP protocol stack and Winsock due to malformed LSP, deletion or incorrect removal of networking software and removal of a malware component which had inserted itself into the winsock, changes in proxy settings, etc. There are some common (but simple) solutions here
which can help resolve connectivity issues.
AdwCleaner previously removed Hotspot Shield
which resulted in loss of Internet Connectivity but since that detection was fixed, loss of connectivity could be due to the removal of a similar third-party VPN software
program as noted in Step 5
or due to one of the reasons noted above.