Hi Mayank ,
You can check once if the user has privileges on the schema which we are selecting . There is no such limitation on the table name but if there is any special character or a suspicious table ,you can filter it using below article .
Also you can enable the debug logging to get more info in the logs -Dscannerloglevel=DEBUG in Metadata load setting JVM option .
Could you please attach the full log here for analysis.
Alternatively you could also raise a GCS ticket with the logs
Raised ticket with Informatica support for this. Workaround for this is to filter out those tables which are causing issue.