There are two possible fixes for the Disk I/O error. The first is to delete and re-create your user folder. The second is to change the permissions for your temporary files.
To delete and recreate your user folder:
- Quit Skype. If you can see the Skype icon in the task bar, right-click it and select Quit Skype. If you can’t see it, right-click the task bar and click Task Manager, then select Skype and click End Task.
- Press the Windows and R keys on your keyboard at the same time.
- In the Run window, type %appdata%\Skype and click OK.
- In the File Explorer window that opens, find the folder with the same name as your Skype Name (if you’re signing in with a Microsoft account, the folder may start with live#3 instead).
You’re about to delete this folder, which means your chat history will be deleted. If you want to save your chat history first, open the folder and copy the main.db file (depending on your Windows settings, you might not see the .db extension) and the chatsync folder to another location. You can transfer them back later, although we can’t guarantee that your entire chat history will be restored.
- Delete the folder.
- Restart Skype and sign in. The folder you deleted in step 5 will be recreated. If you saved your chat history, copy the files back into the folder with the same name as your Skype Name.
If the above solution didn't fix the problem, you may have moved your temporary files to a location outside your profile and are missing some necessary permissions.
Try the following steps. Your temporary folder is located by default at C:\Temp, but you may have set a different location for temporary files.
- Quit Skype (see step 1 above).
- Open File Explorer and go to This PC then find the Temp folder.
- Right-click the Temp folder and select Properties, then click the Security tab.
- Click Edit..., and in the Permissions for Temp window that opens, click Add....
- Make sure the field From this location shows your PC name. If it doesn't, click Locations, select your PC name from the list and click OK.
- In the box Enter the object names to select, type ALL APPLICATION PACKAGES and click Check Names. ALL APPLICATION PACKAGES will be underlined.
- Click OK. ALL APPLICATION PACKAGES is added to the list of accounts able to access the Temp folder.
- Check the boxes for Full control, Modify, Read & execute, List folder contents, Read and Write to grant full control.
- Click OK to close the Permissions for Temp window and OK to close the Temp properties window.
- Restart Skype and sign in.