Magento: “There has been an error processing your request”

Symptoms
The following error message is shown instead of your usual Magento page:
There has been an error processing your request
Exception printing is disabled by default for security reasons.
Error log record number: 1286489434787

Cause
Usually, it is caused by calling incompatible classes in themes, extensions or templates, database connectivity issues or resource shortage (i.e. insufficient diskspace or PHP memory_limit option).

Troubleshooting
The Error log record number shown on the report is just a randomly generated filename, where the actual report data was saved to. Since Magento 1.4 version all error reports are dumped into files by default, rather than showing them right away in browser to every visitor.
To check the generated report you need to login to your Store via FTP or Filemanager, navigate to var/report directory and open the file, named as the error log record number shown on the error page.
The report will provide futher information, the first string in the report is the most important one.

When you see the actual error message, you can look for the solution by narrowing down search results.

If the error report gives no clue, to solve the issue please use the following steps:
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  • Clear cached Magento data
  • Disable Magento Compiler
  • One by one, disable recently installed Magento modules at System > Configuration > Advanced > Advanced > Disable Modules output and flush Magento cache after each operation
  • If you recently installed some theme, try to switch interface to previously used theme or a default theme at System > Configuration > Design, and flush Magento cache
  • Contact Support Team, providing the error log record number and URL, throwing the error report

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