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                                                   EXHIBIT 5
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                               HALE AND DORR LLP
                              Counsellors at Law

                 60 State Street, Boston, Massachusetts 02109
                        617-526-6000 * Fax 617-526-5000



                                 May 14, 1999

Banyan Systems Incorporated
120 Flanders Road
Westboro, MA 01581

     Re:  Non-Qualified Stock Option
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Ladies and Gentlemen:

     We have assisted in the preparation of a Registration Statement on Form S-8
(the "Registration Statement") to be filed with the Securities and Exchange
Commission (the "Commission") relating to 150,000 shares of Common Stock, $.01
par value per share (the "Shares"), of Banyan Systems Incorporated, a
Massachusetts corporation (the "Company"), issuable pursuant to a non-qualified
stock option granted by the Company to a certain optionee pursuant to a written
employment agreement executed between the Company and such optionee (the "Non-
Qualified Option").

     We have examined the Second Amended and Restated Articles of Organization
of the Company, the By-Laws of the Company, as amended, and originals, or copies
certified to our satisfaction, of all pertinent records of the meetings of the
directors and stockholders of the Company, the Registration Statement and such
other documents relating to the Company as we have deemed material for the
purposes of this opinion.

     In examination of the foregoing documents, we have assumed the genuineness
of all signatures and the authenticity of all documents submitted to us as
originals, the conformity to original documents of all documents submitted to us
as certified, photostatic or facsimile copies, the authenticity of the originals
of such latter documents and the legal competence of all signatories to such
documents.

     We assume that the appropriate action will be taken, prior to the offer and
sale of the shares in accordance with the Non-Qualified Option, to register and
qualify the shares for sale under all applicable state securities or "blue sky"
laws.
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Banyan Systems Incorporated
May 14, 1999
Page 2

     We express no opinion herein as to the laws of any state or jurisdiction
other than the state laws of the Commonwealth of Massachusetts and the federal
laws of the United States of America.

     Based upon and subject to the foregoing, we are of the opinion that the
Company has duly authorized for issuance the Shares and such Shares, when issued
and paid for in accordance with the terms of the Non-Qualified Option, will be
validly issued, fully paid and nonassessable.

     It is understood that this opinion is to be used only in connection with
the offer and sale of the Shares while the Registration Statement is in effect.

     Please note that we are opining only as to the matters expressly set forth
herein, and no opinion should be inferred as to any other matters.

     We hereby consent to the filing of this opinion with the Commission as an
exhibit to the Registration Statement in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Securities Act of 1993, as amended
(the "Securities Act"). In giving such consent, we do not hereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act or the rules and regulations of the Commission.

                                        Very truly yours,



                                        /s/ Hale and Dorr LLP
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                                        HALE AND DORR LLP