Hello Bruce,

Please see this link - I think your issue is to do with Google account security, and this KB article should help.

https://support.google.com/accounts/answer/6010255?hl=en

I would start by making sure that the settings in Pegasus are correct for Google security.

Hope this helps

John.

Suddenly I have got the "Host claims that either the username or password you have supplied is invalid" error when getting my mail from Gmail.  I haven't changed anything either in Pegasus or my Gmail password.  I checked that I know my Gmail password by logging in from a browser, then re-typed it into the two settings boxes in Pegasus (incoming and outgoing) but still not working.  thanks, Bruce

You mention Pegasus Mail and Gmail which makes me wonder if this post was intended for the Pegasus Mail Community Support forum instead of the Mercury support forum.  Please clarify if I misunderstand otherwise I suggest a repost in the Pegasus forum.