Welcome to Just Answer
I am a Solicitor and will assist you.
I can understand why you would be concerned as the solicitor would previously held information about you on their files which could put them at an advantage when then acting for your later husband.
Solicitors are suppose to have in place a system whereby they can check the names of potential clients against previous clients so that they can consider whether there would a conflict of interest, such as you have described.
It may well be that in the 18 years since you provided instructions that your solicitor had destroyed your file as files are normally only held in storage for circa 6 years or so. That being said, if the Solicitor had remembered your case, even without the file, then they should have not acted for your further husband.
It is not illegal to act as the Solicitor did, but such issues in relation to conflict of interest are considered professional ethics issues.
Unfortunately as it has been over a year since you instructed that Solicitor you cannot ask the Legal Ombudsman to investigate the matter for you.
You can still refer to the Solicitors Regulation Authority and ask them to investigate, but after 16 years have passed since the solicitor acted for your further husband, in all reality, I do doubt that they will take any action now.
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