RPC server unavailable

[fabrizio]

Hi, we are using PDF XChange Viewer .56 ActiveX component in our application. Our software makes many calls (even one call for each word in the document) to:
DoVerb("Document[X].Pages[X].Text", "Highlight", vDataIn, vDataOut)
in order to highlight words or sentences in a document.
Our customers are experiencing quite frequent crashes/freezing of the PDF component. When a freezing occour in the process monitor we can see PDFXCview process using a lot a CPU and never stopping down. When a crash occour the catched exception is "RPC server unavailable".
In this case the component on the form is offline (showing an icon in the middle).
In the first case (freeze) we need to kill the process and then restart application, in the second restarting the application is enough to get it working again.
Is this a known problem? Is there a way to avoid it? Perhaps adding highlight annotations via javascript?
This is a big issue for us.
Thank for any hint.
Fabrizio

[Vasyl-Tracker Dev Team]

Hi, Fabrizio.

We will investigate and fix this problem... But you may help us accelerate this process. Please for this:
1. Provide simple example code which like to your original code for text highlighting.
2. Please ask your customer for his operation system info and some sample documents for reproducing. Possibly this issue is dependant on some apecific pdf-documents..

Also the step-by-step instructions from customer can be helpful..

And: can you reproduce this issue on your test machines?

Thanks.

[fabrizio]

Hi, the problem is always reproducible, with a little variation on the number of highlights before crash or freeze. No matter the pdf document used as long as a sufficient number of words/sentence to highlight.
The important thing we notice is that the problem can be avoided if the user saves the document after a numebr of highlights. After a document save the component can support a new series of highlights. Perhaps saving the document flushes some data structures within the component? Is it possible to obtain the same without saving? We tried calling FlushDocument but without success.

Basically our code works as follows:

it builds a word list for the document pages calling

AxCoPDFXCview1.DoVerb("Documents[X].Pages[X].Text.Words.Count", "Get", Nothing, vDataOut)

and

AxCoPDFXCview1.DoVerb("Documents[X].Pages[X].Text.Words[" + i.ToString() + "].String", "Get", Nothing, vDataOut)
AxCoPDFXCview1.DoVerb("Documents[X].Pages[X].Text.Words[" + i.ToString() + "].Offset", "Get", Nothing, vDataOut)
AxCoPDFXCview1.DoVerb("Documents[X].Pages[X].Text.Words[" + i.ToString() + "].Length", "Get", Nothing, vDataOut)

then for each word in the list it does some logic and raises an event to highlight the word selected:

vArr(0) = WordElement.iStart
vArr(1) = WordElement.iLength
vArr(2) = iColor
vArr(3) = dAlpha
vArr(4) = WordElement.sAnnotName
vDataIn = vArr
AxCoPDFXCview1.DoVerb("Documents[X].Pages[X].Text", "Highlight", vDataIn, Nothing, 0)

At the end of page X (no more word elements in the list for that page)
AxCoPDFXCview1.SetProperty("Documents[X].Pages.Current", vDataIn, 0)
and start highlighting again.

After 600 to 1000 highlight it breaks down (4 or 5 pages on our typical documents).

[Vasyl-Tracker Dev Team]

Hi, Fabrizio.

Thanks for your example code.

Please update your version to latest (2.0.57 build) - it may resolve your problem.
If not - please let us known about it...

HTH.

[fabrizio]

In build 57 the problem is fixed. Thank you.
Fabrizio

[Tracker Supp-Stefan]

[jstonis99]

Tracker,

We experienced this same issue with one of our Customers. The occurrence was very strange and not very predictable. It occurred when we sent the stream to the activeX to attempt to display the PDF. We could readily reproduce it in one environment but never in others (same versions etc). We were using version .42 when this occurred. We upgraded to .57 and the problem seems to have resolved but our Customer is concerned since we cannot supply the reason behind the randomness of the issue.

Could you provide us with a paragraph explaining under what circumstances you can get the "RPC server unavailable" error?

Thanks,
Jon Stonis
Manager of Product Management
Streamline Health - Cincinnati, Ohio

[Tracker Supp-Stefan]

Hello Jon Stonis,

We are constantly making changes to both our end user products and SDKs.
Sometimes something in an older build is breaking, and it is not in a new one - part of the improvement we have made for another feature could have influenced this bug - as it is now gone we'd rather not waste time investigating why it was caused when it's already resolved.

As for new bugs - we do our best efforts when investigating those, and are usually able to isolate and fix them the same day.
The build with the fix might take a few more days to appear but in time/mission critical and 'Extreme' situations we have also provided developers with custom builds, so we are as flexible as possible, and are looking at existing bugs with all the necessary attention.

Best,
Stefan