A question arose concerning a person who one evening during the Omer received a text message stating, "Today is such-and-such day of the Omer," and this individual, who had not yet counted the Omer that evening, read the message aloud. In effect, this person has counted the Omer and has thus perhaps fulfilled his obligation, such that he cannot then count with a Beracha that night.
At first glance, this is analogous to the more common situation of a person who asks his fellow which number day he should count that night, where Halacha advises the friend not to explicitly state, "Tonight is such-and-such night." If he does utter this statement, he will no longer be able to count with a Beracha, since he has already fulfilled his obligation through this response. Even though the individual had no intention to fulfill his obligation in this manner, some authorities maintain that "Misvot Enan Serichot Kavana" – the lack of intent does not undermine the fulfillment of the Misva. According to these authorities, then, even if one counts the Omer without intention for the Misva, such as by responding to a question or reading a text message, he has nevertheless fulfilled his obligation and may not count that night with a Beracha.
Truth be told, however, in many cases such an individual should, in fact, count the Omer again with a Beracha. As Hacham Ovadia Yosef cites in his work Hazon Ovadia (p. 247), some authorities maintain that one does not fulfill the obligation of Sefirat Ha'omer if he counts only the days, and makes no mention of the number of weeks. For example, if on the eleventh night a person simply states, "Today is the eleventh day of the Omer," without continuing, "which is one week and four days," he has not, according to these opinions, fulfilled his obligation.
It thus emerges that if a person responded to his friend's question by stating simply, "It's the eleventh day of the Omer," he may still count that night with a Beracha, due to the Halachic principle of "Sefek Sefeka," or a "double doubt." Meaning, in this case, two possible arguments could be advanced for allowing him to count with a Beracha. Firstly, according to some views he has not fulfilled his obligation because he made no mention of the weeks. Secondly, even if we follow the view that one fulfills his obligation without mentioning the weeks, some authorities maintain that intention is indispensable for the fulfillment of a Misva, in which case this individual certainly has not yet fulfilled his obligation to count in this case. Hence, given the two uncertainties relevant to this person's situation, he may count the Omer that night with the Beracha.
Hacham Ovadia adds yet another argument, namely, that since we normally count both the days and the weeks, a person who counts only the days clearly demonstrates that he does not wish to fulfill his obligation with this counting. In such a case, he does not merely lack intention to fulfill the Misva, he expresses his specific intent not to fulfill this obligation. All authorities agree that a person does not fulfill a Misva if he performs the given act with specific intention not to fulfill the obligation. Hence, a person in such a case may certainly count again that night with a Beracha, since he counted only the days, without mentioning the weeks, thereby demonstrating that he does not wish to fulfill the Misva at this point.
It should be noted that it is nevertheless customary not to explicitly state the number of that night's counting if one is asked before he had counted with a Beracha. Despite the fact that, as we have seen, starting from the seventh night one who responds by mentioning that day's number may still count with a Beracha, it is nevertheless preferable to avoid this question altogether, and to provide the information indirectly.
Summary: If a person read aloud a text message that stated, "Today in such-and-such day of the Omer" and he had yet to count with a Beracha that night, then if this occurred from the seventh night of the Omer or later, he may still count that night with a Beracha. This applies as well to a person whose friend inquired as to that night's counting and he replied by stating, "Tonight is such-and-such day of the Omer." If this took place on the seventh night or later, he may count that night again with a Beracha, since he has yet to count the weeks.