A recently built server with names instances fails to expand MSDB folder in Integration services. The Error which pops is very generic which can be seen in below image
To get this working you need to update the MsDtsSrvr.ini file with correct sql instance name
<ServerName> ServerName\SqlInstanceName</ServerName>
MsDtsSrvr.ini file can be found at installation Directory\Sql Instance build 90,100,110,120 etc\DTS\bin