An internal error occurred

try Windows file Explorer > View > Deselect preview pane

This is a famous error that I tend to get no matter what version I may be running.  I always seem to get it randomly.

I see this problem constantly if Acrobat X has been open for a while (more than a couple of hours.

ALL of the pdf's I am working with are created on this system, with this user.   There is no protection involved.

I get repeated "An internal error occurred" messages, mostly just a blank message with a blank acrobat window (where the window was populated fine earlier.) 

The error often occurs with a document that I've left open.

Many of the documents, especially the recently created ones are pdf/a, although many are not.

Almost all the documents are scanned and ocr'd so they have large volumes of images.     I do not remember having the error occur specificaly in a pdf that was not a scanned/ocr document, although I will not say it hasn't happened.

There has not been a day that has gone by since installing Acrobat X that this problem has not occurred.

I am trying to use Acrobat as a document processing system to scan index and store documents at a historical society, so this new "feature" of Acrobat X is infuriating and I am just about to downgrade to 9.4

There is another absolutely constant error in Acrobat X, with scanning the back sides of a document, that Acrobat X always cause a fatal error and close, so you lose the 1st side of the document scans.

This happens on multiple scanners in multiple locations.  The scanners are a mix of brand new and old scanners.

Neither of the problems existed in Acrobat 9.     We have not changed anything in the way we work, after upgrading to Acrobat X, we haven't had time to even use any of the new features, all the time has been taken recovering from errors.

No cheers for Acrobat X.   Sort of like Windows Vista ... it looks pretty now, but it doesn't work reliably anymore.

Dear user,

Can you please share this particular file with us, the engineering team would like to have a look at this issue you have reported a bit closely.

My email id is adhar@adobe.com . You can also copy atulagar@adobe.com which is my colleague's email id.

Thanks again for taking the trouble to report this issue. After our investigations are over, we will be able to redress this pretty soon thereafter.

Sincerely,

Atanu Dhar

Which one is the owner to open a pdf file Acrobat X or Reader X? You can check this by double clicking any pdf file and whichever application launches pdf file (Acrobat X or Reader X). If it gets launch in Reader X then try once in sandboxing mode off and then try launching this pdf.

For disable sandbox mode off follow these steps

1. Launch Reader X

2. Go to Edit option -> Preferences-> General

3. There is an option Enable protected mode at start up (Highlighted in the image below)

4. Uncheck the checkbox and quit reader

5. Then try launching your pdf file

Are you facing this error with all pdf files or this specific file?