In April, I attended a scientific conference in the US and so applied and received a 5 year B1/B2 visa. In July, I am supposed to be attending a company training for 2 month. I am wondering whether it is okay to attend the training with my old B1/B2 visa?
"Training" is not the same as formal education. As such you would not need a student visa. However, you should not engage in any paid work on a B1/B2 visa. You should be prepared to prove how you can meet your expenses, including if the company is paying these; evidence of what you will be doing, and evidence of your ties and intention to return to your country of permanent residence. The job you are undertaking training for will be a key reason for you to return.
I can say Yes using my experience:
I have a B1/B2 Visa and I already attended a bunch of internal trainings. I believe the best approach is the company should be responsible by your expenses.
When I need to attend, I get an email from my company inviting me to the training and also explaining the situation. I already have interrogated and I never had problem using this approach.
I am a Salesforce Developer (a specific CRM Software) and once I went to attend a training about this tool. When I said: SalesForce, a red flag came to the interviewer. I needed to show emails, reservations and so on. Also, they call to my boss to make sure. However, I could attend the training.