Thank you for contacting us.
This is a general error and does not provide information regarding the cause of the problem. In the interest of resolving the issue quicker, please do the following: Go to App_Data/Sitefinity/Logs, delete the files there. Reproduce the issue, and archive the newly generated log file.
After that open a support ticket and attach the file and also include information if the issue reproduces with a local copy of the project. Also, does it happen only for blog posts or other content items as well?
Thank you in advance.
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