If you want to backup and convert EML emails, the safest method is to first create a copy of your original EML files before starting the process. Usually, you save the backup on an external device or in the cloud, so the original emails remain unaffected. Then choose a reliable conversion tool that preserves the folder structure, formatting and sender information while doing the process. I tried the TrustVare EML Converter, and it effectively converts batch emails at once. It allows me to transfer old EML folders to PST files without altering any information. It was simple: add EML files, choose the output format, view the data and export.
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