If your wallet is having trouble making peer connections after restarting or upgrading, the "addnode" command may help. With this command you can request your wallet to connect with a node at a specific IP address. But what IPs should you use?
A good source of peer IP addresses for the addnode command is https://www.coinexchange.io/network/peers/QTUM, where they are list “getpeerinfo” data from their Qtum node. To use the IP addresses from this site, and enter them on the Debug window Console as
addnode 188.8.131.52:3888 add
(this is a made up IP address, you should use actual IP addresses from coinexchange . io)
The correct response to the addnode command is “null”, and then your node will try for a minute or two to connect to the peer at that IP address. You can try manually adding 5 or 10 peers. Check the progress in the Debug window - Peers screen.
See more info about using the addnode command in this blog https://medium.com/@jb395official/qtum-peer-connections-may-21-2018-ba12bda71e4f