I was deposed by IRS investigators in a criminal case. The investigators found a copy of my software on a seized computer and asked what my relationship was with the (now in the care of the government via incarceration). Once I explained the connection, I was thanked and left alone. The person was convicted of fraudulent return as they were filing for their clients (recent immigrants) and capturing their refunds, which has been improperly inflated via EITC. The convicted sent me threatening messages, even though I had no information for or against their case, but which the prosecutor likely found "helpful".
The OP is a good reminder to research electronic record keeping regulations, and to try to ensure your actions do not give blanket search and seizure rights to the IRS. Not only for your client's protection, but simply to protect your ability to do daily business. As I have likely posted many times, not being able to provide PRINTED records, or simply acting in a way to show your record keeping is electronic, may (definitely in the past, and possibly with current regs unless they have been revised) give the tax agencies any time warrant-less search rights, and requires proactive notification to the IRS if there is any chance required data is unavailable.