This is due to a recent update with Citrix Workspace App. If you don't need to have that application installed on your PC, remove it. If you must have it installed - uninstall it and reinstall it but leave the "App Protection" option unchecked.
They have a bug due to improper handling of the HC_NOREMOVE message code. Details here
We have a workaround in place for Monday's release of Toad 14 beta. However, to work around it, Toad must also handle that message code improperly, so to activate the workaround you must enter this in your Toad.ini file under the [SETTINGS] section. We haven't yet found any ill effects of the workaround, but we are being cautious about it.
CitrixWorkspaceAppWorkaround=1
This was also brought up here.