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What version of Exchange?<br />
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If it's 2010 or higher you can try a mailbox repair request.<br />
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<a href="https://technet.microsoft.com/en-us/library/ff625221(v=exchg.141).aspx" rel="ugc">https://technet.microsoft.com/en-us/library/ff625221(v=exchg.141).aspx</a><br />
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Since you did a new profile, and can use the nickname file on another computer, that's about all you have left besides trying a new Windows profile on that machine.
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They are running Outlook 2010 and the e-mail is Office 365 Exchange Online. &nbsp;Like I said it worked fine when I merged it to another PC's Outlook. &nbsp;To my knowledge, the autocomplete is separate from the actual Exchange mailbox.
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Autocomplete corrupts fairly easily. If broken, the only solution is to delete and allow it to rebuild. I keep all my important email addresses in my Contacts so that I have them if needed.
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But if the autocomplete were corrupt, then how is it working on a separate machine using the same .dat file? &nbsp;I've tried backing up the .dat file, removing the outlook profile, re-adding the email account, and then using Nk2edit to import the .dat. &nbsp;This will work on any other machine which implies that the autcomplete file is not corrupted it's something to do with Office on the problem computer.
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Dear User,<br />
<br />
Few days earlier, I was having the same problem. When I searched about my error &quot;Could not complete the operation. One or more parameters are invalid.&quot; on Google, then I get an informative Article on same error message <a href="http://www.pstrecovery.net/blog/could-not-complete-the-operation-one-or-more-parameters-are-not-valid-outlook.html" rel="ugc"><b><b></b>http://www.pstrecovery.net<wbr />/blog/coul<wbr />d-not-comp<wbr />lete-the-o<wbr />peration-o<wbr />ne-or-more<wbr />-parameter<wbr />s-are-not-<wbr />valid-outl<wbr />ook.html</b></a>. <br />
<br />
Thanks &amp;&nbsp;Regards<br />
Edwin Hoffer
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@DenTechCO - Thank you and I was happy to help.
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I am unable to send e-mails from my Outlook autocomplete list. &nbsp;When I add an address from there and hit send I get a message, &quot;Could not complete the operation. &nbsp;One or more parameters are invalid.&quot; &nbsp;All the solutions online are to clear the autocomplete history, which kind of defeats the purpose. &nbsp; I have tried removing and re-adding the Outlook profile and running a full repair on Microsoft Office as well as trying to send from safe mode. &nbsp;After each attempt I get the same error. &nbsp;To make sure the autocomplete file wasn't the issue I copied it over to a different PC and used NK2Edit to successfully merge it, and I can send from the other machine fine.
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I am unable to send e-mails from my Outlook autocomplete list.  When I add an address from there and hit send I get a message, "Could not complete the operation.  One or more parameters are invalid."  All the solutions online are to clear the autocomplete history, which kind of defeats the purpose.   I have tried removing and re-adding the Outlook profile and running a full repair on Microsoft Office as well as trying to send from safe mode.  After each attempt I get the same error.  To make sure the autocomplete file wasn't the issue I copied it over to a different PC and used NK2Edit to successfully merge it, and I can send from the other machine fine.

Outlook Autocomplete Not Working

Microsoft Outlook is a personal information manager from Microsoft, available as a part of the Microsoft Office suite. Although often used mainly as an email application, it also includes a calendar, task manager, contact manager, note-taker, journal, and web browser.

Outlook

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.