AVG antivirus scans the data of your device and provides protection from all kind of cyber threat like malware, spyware, rootkits, Trojans and ransomware etc. It detects the dangerous websites and spam emails. You can install this antivirus through www.avg.com/retail. This error is also known as Update is already running. It occurs when AVG antivirus fails or crashes. This will appear as an annoying notification on your screen.
Resolve AVG error code 0Xe001D026:

Method 1: Close the Conflicting programs:
First you have to open Task Manager by clicking Ctrl-Alt-Del. Then you will observe the list of programs currently running. Then, go to the Processes tab and stop the programs one by one and then click on the End Process button. Now see if the error reoccurs each time you stop the process. When you know which program is causing the error, go to the next step, by reinstalling the application.
Method 2: Update/ Reinstall Conflicting Program:
For reinstalling, on Windows 7 you have to click on the Start Button, then click on Control panel, then Uninstall a program. For Windows 8, you have to click on the Start Button, then scroll down and click More Settings, then click Control panel > Uninstall a program. For Windows 10 type Control Panel on the search box and then click Uninstall a program. Then in Programs and Features menu, click the problem program and click on Update or Uninstall. You just have to follow the instructions to complete the process, however if you chose to Uninstall, you will follow the prompt to uninstall and then re-download application’s to reinstall the program.
Method 3: Update your Virus Protection Program:
To prevent your computer from this error, you have to update your virus protection program and run the scan on your PC, and also run the window update.
Method 4: Reinstall Runtime Libraries:
For this you have to go to Programs and Features, and find and highlight the Microsoft Visual C++ Redistributable Package. Then, click on Uninstall, and when it is done, reboot your computer. At the end, download the latest redistributable package from Microsoft then install it.
Method 5: Run Disk Clean up:
For this, consider your backing up files and make the space on your hard drive. Clear your cache and reboot your computer. Or you can Run Disk Cleanup, open your explorer window and right click your main directory (this is usually C:). At the end, click on Properties and then click on Disk Cleanup.
Method 6: Reinstall your Graphic Drivers:
For this, you have to open your Device Manager, and then locate the graphics driver. At the end, right click the video card driver and then click on uninstall, and restart your computer system.
Method 7: IE related Runtime Error:
If the error is related to the Internet Explorer then reset your browser and disables script debugging and error notifications.
But if this method do not solve your problem you can contact to the customer care executives of AVG team via www.avg.com/retail.