After two delays that prevented SpaceX from carrying out a Falcon 9 mission on Sunday and Monday, the company may try again tonight. SpaceX typically hasn't encountered multiple delays of this sort. The first was triggered by an issue with the rocket's computer guidance system.
We're going to spend the 4th doing a full review of rocket & pad systems. Launch no earlier than 5th/6th. Only one chance to get it right …— Elon Musk (@elonmusk) July 4, 2017
This mission is going to bring the Intelsat 35e communications satellite to orbit. Due to the weight of the payload and the fuel that's required for the core mission, SpaceX won't be able to recover the rocket for future use.
Out of an abundance of caution, SpaceX will be spending the Fourth of July doing a full review of the rocket and launch pad systems. The next launch opportunity for Intelsat 35e … is now no earlier than Wednesday. - SpaceX
To make sure serious accidents are avoided, the company performed thorough checks on July 4.