The main causes for invalid XML and other related errors are many; mostly the file corruption of PST folder. The file corruption can be due to many reasons like:
• A newly installed add-in can corrupt the Outlook.pst file.
• Newly installed add-ins can be causing issues in accessing the Outlook.pst file.
• Anti-virus installed on the computer system is blocking the PST file.
• Virus has infected the PST file because of which the file is corrupted.
• Sudden power failure has corrupted the file’s index.
• There are many more reasons for a file corruption
Solution for the issue
The easiest and cheapest solutions for resolving the PST file corruption and the related issues are to recreate the Outlook profile and PST file. This solution can be tried only if the user is sure that the damaged PST file does not have any important email items, contacts, notes, to-do-list, or drafts. If the corrupted PST file contains any important messages and other data, the chances are more of losing them during the recreation. This will leave the user gain without any hope about the files. As of now, there is no option for retrieving the lost messages and other items.
Other solutions for the PST corruption issues:
• Backup the PST file – before installing any new add-ins back up the PST files. Once the add-ins arte installed and if any error message is being shown about PST corruption, then un-install the add-ins and restore the backup file.
• Scanning the computer system – scanning the system periodically will find possible virus and malware threats. This will help in protecting the Outlook program and the PST file form damage.
• Third-party Repair PST tool – these tools will help in repairing the damaged PST file.
• Kernel for Outlook – this software is cheaper yet efficient repair tool for PST file corruptions. It scans the damaged PST file, repairs the file, and recovers all email messages, notes, calendars, and other data in the same format as they were before corruption.
If you doubt that your Outlook PST file is corrupted, follow the instructions of this article. Google+