Hi there,
SearchIndexer.exe is the Windows service that handles indexing of your files for Windows Search, which fuels the file search engine built into Windows that powers everything from the Start Menu search box to Windows Explorer, and even the Libraries feature. I suspect there might be a corruption in indexing the System, you can try indexing the Pc again and run SFC & DISM commands.
Hope this answers all your queries, if not please do repost back.
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