App pool defaults explained

good article on app pool values:

http://www.iis.net/configreference/system.applicationhost/applicationpools/applicationpooldefaults

The URL 'Shared Documents/file.pdf' is invalid. It may refer to a nonexistent file or folder, or refer to a valid file or folder that is not in the current Web

you wont be abl to load any files in the library/list

check the log files of sharepoint first.

if the logs say that for the database the 'PRIMARY' filegroup is full you will need to delete some data from that site. the primary file group size might be in few kbs and it wont allow you to delete any files from the sharepoint server also. if you are able to delete from the site start with very small size files and simultaneously clear them from the recycle bin.

check for disk space on sql server and then clear out the sql logs.

an error occurred while rendering navigation for requested url sharepoint 2010 userprofileapplicationproxy

Issue:An error occured while rendering navigation for requested URL: <removed>. Exception message: Object reference not set to an instance of an object. Stack trace:    at Microsoft.Office.Server.Administration.UserProfileApplicationProxy.get_ApplicationProperties()
   at Microsoft.Office.Server.Administration.UserProfileApplicationProxy.get_PartitionIDs()

resolution:

• Go to "Central Administration"
• Go to "Application Management" > "Configure service application associations"
• Click "Default", and then uncheck the UPS from there

this is an better option as opposed to deleting the UPS altogether..just do an iisreset after the disassociation in case it is not working...

if you have the liberty to delete the UPS and recreate it again you can do that as well.

in my case this happened when the servers were migrated to another domain..the UPS was created under olddomain\login hence the issue. 

Cannot apply security settings to resource HKEY_LOCAL_MACHINE\Software\....as it does not exist.

To resolve this issue, you must uninstall SharePoint 2010 FIS Enterprise from each server. Then, you must use a new FIS activation key to reinstall SharePoint 2010 FIS Enterprise on each server. To do this, follow these steps: 

1. Back up your current environment.
   
   This backup is to make sure that you have a safe copy of your data or for you to try this operation first on a set of test servers. We strongly recommend that you try this operation on test servers before you run it in production.
   
   For more information about how to back up your current environment, visit the following TechNet website:
   http://technet.microsoft.com/en-us/library/ee428315.aspx
2. Uninstall the current product from Control Panel, and then restart your computer.
   
   Note You do not have to uninstall any of the Microsoft SharePoint prerequisites.
3. Install by using the correct license type.
   
   Note You do not have to install any of the Microsoft SharePoint prerequisites.
   
   To install by using the correct license type, follow these steps:
   1. Log on to your account, and then retrieve a new SharePoint 2010 FIS Enterprise product key from the following website:
      https://www.microsoft.com/licensing/servicecenter/
      Note You have to obtain a new key. You do not have to download new installation media.
   2. For more information, see the following articles on the Microsoft TechNet website:
      http://technet.microsoft.com/en-us/library/cc262243.aspx (Single Server)
      http://technet.microsoft.com/en-us/library/ee805948.aspx (Multiple Server farms)
4. Verify that the correct license type is installed by using the SharePoint Management Console. To do this, follow these steps:
   1. Click Start, click All Programs, click Microsoft SharePoint 2010 Products, and then click SharePoint 2010 Management Console.
   2. In SharePoint 2010 Management Console, at the command prompt, type the following command, and then press ENTER:
      (Get-SPFarm).Products
   3. Make sure that one of the following GUIDs exists in the list:
      • B2C0B444-3914-4ACB-A0B8-7CF50A8F7AA0
      • D5595F62-449B-4061-B0B2-0CBAD410BB51
   4. Make sure that neither of the following GUIDs exists:
      • 1F230F82-E3BA-4053-9B6D-E8F061A933FC
      • F48AC5F3-0E33-44D8-A6A9-A629355F3F0C
5. Restore your data. For more information, see the instructions in the following Microsoft TechNet article:
   http://technet.microsoft.com/en-us/library/ee428303.aspx

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