Topic: Xref get corrupt, even without opening the file

[huiz]

A few months ago a colleague showed me a problem with a project. He got a drawing from an architect, inserted in our business template, cleaned it a little, saved it and used it as an xref. After plotting he reopened the drawing and got an error on that particular xref. It was corrupt and he tried recovering it. Thousands of error notifications were scrolling by. After that, all lines were places on layer 0, all blocks and texts were replaced by table objects.

A weird situation because it was not able to reproduce the error. But since then he gets this particular problem regularly, about once or twice a month. I also once got this problem once, and this morning another colleague too. He included a drawing as an xref, he did not open that one at all, and still the xrefed file is corrupt. I include it in this post.

It seems to happen in AutoCAD 2010 and 2011.

This is a piece of 11.000 error notifications:

Code: [Select]

AcDbBlockReference(17C7F)         Null Layer            Redirected
AcDbDictionary(17C81) AcDbRepData ePermanentlyErased    Delete Entry
AcDbBlockReference(17C89)         Null Layer            Redirected
AcDbDictionary(17C8B) AcDbRepData ePermanentlyErased    Delete Entry
AcDbBlockReference(17C93)         Null Layer            Redirected
AcDbDictionary(17C95) AcDbRepData ePermanentlyErased    Delete Entry
Pass 2 21100   objects auditedAcDbText(17CE7)                   Null Layer     
      Redirected
AcDbLine(17CEC)                   Null Layer            Redirected
AcDbText(17CED)                   Null Layer            Redirected
AcDbLine(17CF3)                   Null Layer            Redirected
AcDbLine(17CF3)                   Null Linetype         Redirected
AcDbText(17CF4)                   Null Layer            Redirected

Anyone has the same problem? Or an idea to solve this? Or a clue? Or tips? Prayers?

[mjfarrell]

can I see a copy of the uncorrupted file?

it would appear that audit/recover thrashed some objects, that is my first impression

the objects are most likely dynamic blocks

[huiz]

Attached the uncorrupted file:

[mjfarrell]

OK, I've seen the file...
performed both a(n) Audit and a Recover on it...autocad reports NO errors...

interestingly, the file appears to be a survey and I wonder did theis DWG originate in Civil 3D, or some other application that can write a dwg format file?

Later I will experiment with it as XREF and attempt to make it go bad, and report back if I can make it do so.
Do you know if they are using a copy of the XREF file locally? Check the XLOADCTL variable to verify.

[huiz]

This is indeed a survey but created in AutoCAD. But the error also happen with architectural designs we receive from other persons. There is only one thing they share and that is the business template, which we use for years. The template get upgraded every version of AutoCAD but there are no strange things in it. Also, we create 5000 drawings a year and only 10 or 20 or so get corrupted like this.

We have turned off visual fidelity, but it should not affect drawings in AutoCAD 2010 format. Also we use demandloading Xrefs with copy. A lot of drawings need to be edited while being referenced. But we have that for years and never gave errors.

[mjfarrell]

I'm still looking at this.
From your last; I'm gettting the impression it could be a network latency issue while performing a save of the file and the refedited file back to server.  There is not an easy way to test or verify this supposition.

[huiz]

Indeed difficult to find out the bug. I thought so too about a network latency but I'm not sure. It does not happen very often. It is always an xref, not a normal drawing (which is also saved on a network disc). It seems to be a problem in the layertable, blocktable, etc. Lines are drawn correct, only texts, blocks and other things are corrupted. And all elements seem to miss layer information. If I open the drawing in BricsCAD (which is sometimes more careless in error checking) there is not even layer 0! A complete empty layer list.

But as far as I understand it is not a common problem. There aren't tens of people who claim to have this problem too :-)So I hope you or someone else have some clues, but don't spend too much time on it. Thanks anyway!

[DATHAN.NEAL]

We have had this issue for probably 3 years. It happens probably once every 3 weeks or so. Did you guys ever find out what was causing this issue?

[mjfarrell]

have we looked at the settings for INDEXCTL
and XLOADCTL

XLOADCTL
0
Turns off demand-loading; the entire drawing is loaded.
1
Turns on demand-loading. Referenced drawings are kept open and locked.
2
Turns on demand-loading. Copies of referenced drawings are opened and locked; referenced drawings are not locked

INDEXCTL

0
No indexes are created
1
Layer index is created
2
Spatial index is created
3
Layer and spatial indexes are created

3 is recommended setting