Effects concerned (ability to communicate) would be very low.
HOW IT COULD NOT SUCCEED:
It would not effectaffect people. Professionals all around the world are keeping up with their respective fields more o less. Technology concerning, only latest research (5-10 year years, 15 max) wouldcould be lost. Also keep in mind that research papers are usually literary kept as papers in university libraries.
if it would not affect even turned off computers, technological impact would be even less. In all filed you have thousands of students caring theytheir laptops filed with latest knowledge. chances that some of them would have their laptops turned off at time of attack are close to certainty.
HOW IT COULD SUCCEED:
however, it would greatly impact out 'organization'. Databases oof people, logistic databases etc. You would looslose all kinds of data from lent books in library to who has access to security facilities. Everybody would know who is president without Wikipedia, but let's take Universities, you know don't know who are students, what marks they had, etc.. You would also lose most digital contracts, etc.. Minor a occasionally major social chaos would occur, and that could escalate into conflicts.
it would stop us for a while. Top scientist could not continue their researches further, but would need to focus on restoring our knowledge bases from their memories and fragments of surviving data. Put together with 1) it would mean we would be stuck for a while.
SUMMARY:
It has little to no chance to make us unable to communicate technologically, but it could realistically succeed butby enduring chaos a making us unable to cooperate on answer.