Are you using Accpac Plus in addition to Adagio? If so, are there any Lanpaks installed with Accpac Plus?

The error 1305 indicates that you are trying to use Adagio and are unable to gain access to the EZTASKS.LD4 file. I mention the above scenario because if Accpac Plus is in use without a Lanpak, it locks the EZTASKS file to the exclusivity of all other functions (including itself!). The 'solution' in this case is either to (purchase and) install a Plus Lanpak, or do not use both applications simultaneously.

If you are not using Accpac Plus simultaneously with Adagio, then you should focus your search on network and workstation rights to opening and editing this file. It may be that you are logged into the network without write 'rights' to the \softrak\system directory (or whichever path you specified as your EZTAKSKS path).

You mentioned in your post that read-write is likely not the problem, so I am going to assume that Accpac Plus is the culprit.

For you or any others reading this post, if you wish to use Adagio simultaneously with Accpac Plus, the 'EZTASKS path' should be \ASP. If you are using Adagio without Plus, choose \Softrak\System.