In such cases, where you have a large number of PST files and you want them to be merged into one single. Well, in that case, the manual trick may not work successfully because of plenty of files, which may cause errors or other kinds of interruptions. In such cases, you should try a professional solution that merges PST files into one single file without error or interruptions. Download a free version of this PST Merge software to merge PST files into a single file.
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PST Merge Software