ost to pst convertes

[Blackwellwalker]

Hi,

My user used exchange in the past and now uses pop3 client... 
exchange doesn't exist anymore. her new pop client only has one 
pst data file... one can't import the ost files.  How convert ost 
to pst?

Need OST to PST Converter recommendations

Due to hard drive fails, i lost my data. But i need to recover 
mail data from office 365 outlook 2013. So, i need a some OST to 
PST converter recommendation, if you have used a good one. Thanks 
in advance for your time and recommendations!
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