I would like to connect my old SCSI coolscan iii

You've not said what the message is but I suspect that the software is too old to be used on the macbook if it is running OS X 10.7 (Lion) or if you are running snow leopard, it may be a non-intel version of the software. It may be asking you to instal rosetta which would be on your snow leopard instal disk.

If the Nikon website does not have updated software you could try vuescan which according to this page http://www.hamrick.com/vuescan/nikon_coolscan_iv_ed.html does work with the film scanner and you can download a demo version which you can trial before you buy. Hope this helps.

http://www.sebsgarage.com/2005/11/cleaning-nikon-coolscan-iv-ed-ls-40-film-scanner

I read this forum entry and it solved my problem also:

http://www.pcreview.co.uk/forums/thread-1936922.php

http://cgi.ebay.com/MAC-Dock-USB-SERIAL-to-SCSI-iMAC-iBOOK-G3-G4-G5-NEW-NIB_W0QQitemZ220357580162QQcmdZViewItemQQptZPCA_Cables_Adapters?hash=item334e55d582&_trksid=p3286.c0.m14

Try a good scanner program called vuescan. Much better than Nikon software. I have been using on XP for a long time and no problems

This is a problem with SCSI bus speed too fast for the legacy device. The recommended SCSI controller is the Adaptec 2906, which will recognize legacy devices and slow the bus speed for them.

You also need an older ASPI driver set, version 4.70 available from Adaptec at http://www.adaptec.com/en-US/speed/software_pc/aspi/aspi_v470_exe.htm

Before you install the 4.70 version you need to be sure to remove any newer versions of these files: Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}ASPI32.SYS Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}WOWPOST.EXE Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}WINASPI.DLL Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}WNASPI32.DLL

These files may be found in WindowsSystem or WindowsSystem32. In order to delete them, you will need to restart your PC in Safe Mode. Once they are gone, restart your computer normally and run the ASPIINST.EXE program which was extracted by running the file downloaded from Adaptec.

Finally, you need Nikon Scan 3.1.2 for the LS-2000, available at http://support.nikontech.com/app/answers/detail/a_id/81

I had the same problem. You must remove the cover on the scanner. The reading unit shuld be moving on two metalleaders. It was the oil on them that was dry so i had some oil on and helpt it moving with my finger. Now its working again!

Good luck! Bjarne

Yes - get hold of an Adaptec USB2XCHANGE SCSI-USB cable and download Vuescan software (www.hamrick.com). This works perfectly on LS2000 - Macbook Pro combo. 

Here's what you need to do (carefully!!):

www.vad1.com/photo/dirty-scanner/ls2000-cleaning/

I know some devices may not work properly or will not work period if your running a 64 Bit processor. I would recommend to contact the manufacture of your scanner & verify this. Possibly they may have 64bit drivers. Hope this was any help to you.