<div>
<a href="http://msdn.microsoft.com/en-us/library/dd576268%28v=office.12%29.aspx" rel="ugc">http://msdn.microsoft.com/en-us/library/dd576268%28v=office.12%29.aspx</a><br />
<br />
Search for &quot;Figure 8.10 The Additional Lock Information Box&quot; read about the Locks <br />
<br />
You can tell SharePoint to do certain things when quotas are hit. Such as make all read-only(Blocks additions, updates, and deletions)<br />
<br />
Hope that helps you 
</div>


http://msdn.microsoft.com/en-us/library/dd576268%28v=office.12%29.aspx [http://msdn.microsoft.com/en-us/library/dd576268%28v=office.12%29.aspx]

Search for "Figure 8.10 The Additional Lock Information Box" read about the Locks

You can tell SharePoint to do certain things when quotas are hit. Such as make all read-only(Blocks additions, updates, and deletions)

Hope that helps you

<div>
<div class="content wysiwyg-content">
My site collection suddenly stop working and after investigating into it I found that the 'Site Collection Quotas and Locks' under 'SharePoint Site Management ' was suddenly changed to 'Read-Only' automatically. <br />
<br />
Can anyone please let me know how this can be triggered and set to 'Read-Only' mode.
</div>
</div>


My site collection suddenly stop working and after investigating into it I found that the 'Site Collection Quotas and Locks' under 'SharePoint Site Management ' was suddenly changed to 'Read-Only' automatically. 

Can anyone please let me know how this can be triggered and set to 'Read-Only' mode.

Site Collection Quotas and Locks (Read-only)

Microsoft applications include a variety of software programs, including development and digital authoring programs (Expression and Media Center), educational programs, Internet software, including Essentials, Skype and the Live family, anti-virus, productivity applications and suites like Office, Excel, Word, Outlook, Access and PowerPoint, video games and server applications such as Exchange, SharePoint, IIS and Virtual Server.

Microsoft Applications

Microsoft Sharepoint is a software platform and family of software products used for collaboration and web publishing combined. These capabilities include developing web sites, portals, intranets, content management systems, search engines, wikis, blogs, and other tools for business intelligence and collaboration. SharePoint has a Microsoft Office-like interface, and it is closely integrated with the Office suite.