Police say they'll work with marshals to prosecute people who venture onto closed roads.
They issued the warning after a number of reports this week.
Officers say riding, driving or walking onto the course while it's closed puts yourself and others at serious risk.
They say if you defy the law, you might find yourself appearing before the next available court.
Memorial service tonight for ferry lost in WW2
The memorial service to a Steam Packet ferry sunk during WWII will take place this evening.
Biker stopped doing 70 in 50 zone - with pillion
Police are reiterating warnings about speeding after three more riders were caught at more than 70mph in a 50 zone.
Doug Barrowman company dissolved
A company founded by Island businessman Doug Barrowman has been dissolved.
Laxey lights to go poo-powered?
Could Garff soon be lit by dog mess?
Photo appeal so late TT rider's children can remember him
The wife of a TT rider who lost his life in a crash this week is appealing for pictures his two children can remember him by.
Cannabis club conquers nasty niff worse than spliff whiff
A cannabis social club in Ramsey says it's discovered what's causing a nasty smell to seep into its premises.
Heysham's MP posts video about "absolute chaos" Heysham traffic
Heysham's MP says she's had more than 100 complaints about heavy traffic around the port, which has been highlighted during TT.
UK's fuel duty cut extended
The government says the temporary reduction in fuel duty is being extended to help motorists and businesses.
