Businesses Stay Optimistic Amid GSTN's Tech Hiccups ET speaks to stakeholders as portal tries to smoothen glitches related to filing of returns System seems to have encountered an error while processing your return...Please try after some time. GSTN portal is experiencing an abrupt surge in traffic, hence we're unable to service your request...' These are some of the responses from the Goods and Services Tax Network (GSTN) portal when businesses attempted to file returns or upload invoices for July. Filing returns has emerged as a sore point after GST rollout on July 1, pushing the portal's functioning to the centrestage at the last GST Council meeting on September 9. A group of ministers headed by Bihar finance minister Sushil Kumar Modi has already directed Infosys -the backend service provider -to fix the system. Why did GSTN crash on September 4 and September 9? The portal is designed handle uploads of up to 50,000 invoices per second. Was it server capacity o