topic Cannot access, error locking DWG when attaching a source drawing in Map Explorer in AutoCAD Map 3D Forum

Cannot access, error locking DWG when attaching a source drawing in Map Explorer

bill_smoker — Fri, 22 Aug 2025 09:03:19 GMT

We frequently use spatial queries to bring in base data from source drawings. One user keeps getting this error when attaching a drawing in Map Explorer (task pane).

Cannot change active status of dwgname.dwg

Cannot access dwgname.dwg

Error locking dwgname.dwg

I assumed that they didn't have RW permission to the source folder, so was unable to create lock files. The odd thing is that they DO have RW access, can create & delete files etc. Other users with the same admin rights don't have this issue.

Pretty sure that it is a permissions issue within Windows rather than AutoCAD but I can't find a solution. Any ideas?

Re: Cannot access, error locking DWG when attaching a source drawing in Map Explorer

ChicagoLooper — Sun, 24 Aug 2025 13:07:43 GMT

@bill_smoker

Sounds like another user could still have CPZ_Z_ASSETS.dwg attached in to an earlier query. That user needs to Detach or Deactivate so the drawing so it's unlocked. Other users cannot access a locked dwg.

Or the user himself, the one getting the error message, has the drawing open. That's a no no!

He must close the drawing because M3D won't attach an open file. If he needs that drawing open when running a query, then he can make a duplicate right before attaching to Map Explorer. <<He wants the duplicate to be super up-to-date, current.>> When running the query, attach the original so he can keep the duplicate open. Don't forget to 'detach' the original from Map Explorer when finished. Also, be be sure to detach and delete the duplicate too, you don't want two dwg's of the same file. The existence of a no-longer-needed duplicate will always cause confusion and confusion might be co$tly for you and the client.

Re: Cannot access, error locking DWG when attaching a source drawing in Map Explorer

O_Eckmann — Mon, 25 Aug 2025 13:29:17 GMT

Hi @bill_smoker ,

You have to test step by step.

1. On this PC open a session with non problematic user name and try to attach file :

it's not OK => problem with OS => rebuild PC (or check out / check in AD)

it's OK => step 2

2. On a PC without problem, open a session with problematic user name and try to attach :

it's OK => pb is on 1st PC => delete / rebuild widows profil for problematic user name

it's not OK => pb of write access => step 3

3. Delete AD profil User and rebuild by copy of another user, then affect right to new user profil and test.

Re: Cannot access, error locking DWG when attaching a source drawing in Map Explorer

bill_smoker — Tue, 26 Aug 2025 07:14:41 GMT

This is all good advice, but not applicable in this case. The DWG is not in use by anyone else, and no lock files are present.

Re: Cannot access, error locking DWG when attaching a source drawing in Map Explorer

bill_smoker — Tue, 26 Aug 2025 07:16:35 GMT

Excellent advice, will try this at the first opportunity. User has now reported similar issues with other software, so it increasingly looks like a user permissions problem.