The AGM was interrupted because of problems with voting machines. The company said, "This malfunction was very probably caused by a hacking attack on the voting system."
Vivendi's minority shareholders said they would ask the courts to seize the hard disc that recorded votes at its AGM, adding that they would appoint experts to examine the hard disk.
"To say that the votes are nullified has very serious consequences, it means that accounts are not approved and therefore dividends cannot be paid," said ADAM spokeswoman Colette Neuville.
The company has rescheduled its AGM for 3 June.